Brass life: How to determine max charge so primer pockets survive a sufficient nr of reloads (at least 10)?

[NamibHunter]

I realize that new brass benefits from fireforming to your chamber, using a medium load that does not blow out the primer pocket on the first firing. The first firing hardens the case head and buys you longer brass life.

My question is how do you decide on the powder load for fire forming: Two grains above book minimum or two of three grains below book max?

Also: Do you guys measure the expansion in the web diameter, using a micrometer that can read accurately down to 0.1 thou? Measure before you FL resize or after? That seems to change the measurement by 1-1.5 thou.

How much web expansion do you expect to see on the first firing, and how much on subsequent firings? What is too much?

Idea being that we figure out how fast we can run, and still allow the LRP primer pockets to survive at least 8-10 reloads. Using Norma and Nosler brass in 300 WSM. So Lapua/ADG/Peterson are not available.

One trick i read about is to take a set of pre-weighed containers of powder to the range, say 2.0 grains apart (like 64.0, 66.0, 68.0 gn), starting middle of range, and sacrifice one case by loading it with successively higher powder loads at the range until [Edit:] the primer gets way too easy to seat (or falls out after seating). [I guess the benefit of using the same case is that you can feel how primer seating force reduced at every reload, and all of this is of course done in one trip to the range. And you lose one case in the process, not multiple cases.] Presumably using a neck sizer and an arbor press, and a priming tool. Has anybody tried that? [Not recommending this to anybody, and i agree it sounds rather unsafe!]

 

[hafejd30]

Your “trick” looks like a great way to push past safe pressure limits if your waiting for the primer to just fall out. Possibly resulting in catastrophic failure

Personally I take virgin brass, maybe run a mandrel through it. Then load it and find the best load the virgin brass shoots. Then shoot and practice with.

Once I get through the virgin brass or enough of it to test then I’ll retest. I let my rifle tell me what it wants to shoot. Some shoot better faster some slower.

If your looking for long range performance then velocity and BC are your friends. Chasing higher velocity generally results in higher pressure and less case life. Some case like hornady or federal tend to give out before quality brass like Lapua

Just play within the limits and watch for pressure signs when creeping up the powder charge.

Brass is like barrels. If you want performance you’ll likely sacrifice life

So buy more brass when needed

If your truly concerned about brass life then two steps will help you

1) Load on the lowest node. If the rifle shoots good at 2650 FPS and 2850 FPS the 2650 will likely result in better brass life. With long range performance as a trade off

2) The second way to conserve brass……Don’t shoot……

 

[KnowNothing256]

Your “trick” looks like a great way to push past safe pressure limits if your waiting for the primer to just fall out. Possibly resulting in catastrophic failure

Personally I take virgin brass, maybe run a mandrel through it. Then load it and find the best load the virgin brass shoots. Then shoot and practice with.

Once I get through the virgin brass or enough of it to test then I’ll retest. I let my rifle tell me what it wants to shoot. Some shoot better faster some slower.

If your looking for long range performance then velocity and BC are your friends. Chasing higher velocity generally results in higher pressure and less case life. Some case like hornady or federal tend to give out before quality brass like Lapua

Just play within the limits and watch for pressure signs when creeping up the powder charge.

Brass is like barrels. If you want performance you’ll likely sacrifice life

So buy more brass when needed

If your truly concerned about brass life then two steps will help you

1) Load on the lowest node. If the rifle shoots good at 2650 FPS and 2850 FPS the 2650 will likely result in better brass life. With long range performance as a trade off

2) The second way to conserve brass……Don’t shoot……

No offense, but that’s a lot of words to not answer the question at all. The only thing you said was “to conserve brass, shoot min load.”

 

[acudaowner]

unless you over clean a primer pocket and remove too much metal , there are ways to tighten them back a bit


unless you see case head separation , I don't worry about my brass so much . I have 6k pieces of factory hornady some that I have shot 6x's , and cross my fingers no problems so far so good . treat it like gold but enjoy it .

 

[lash]

Brass life: How to determine max charge so primer pockets survive a sufficient nr of reloads (at least 10)?

I realize that new brass benefits from fireforming to your chamber, using a medium load that does not blow out the primer pocket on the first firing. The first firing hardens the case head and buys you longer brass life. My question is how do you decide on the powder load for fire forming: Two...

www.snipershide.com

Well, to be honest, you didn’t answer the question either. How exactly should one answer that particular question if one doesn’t push the brass to max speeds and pressures?

I know that personally, I’m not looking for a magic number of reloads for my brass. Admittedly, I’m not pushing max speeds either. I find where there appear to be nodes and where I start seeing pressure signs and then back down one node to a speed that my barrel likes. I also get really good barrel life this way.

I’ll have to read what some do that like to push to the ragged edge. It’s no problem for me how you choose to use your expendables.

 

[KnowNothing256]

Brass life: How to determine max charge so primer pockets survive a sufficient nr of reloads (at least 10)?

I realize that new brass benefits from fireforming to your chamber, using a medium load that does not blow out the primer pocket on the first firing. The first firing hardens the case head and buys you longer brass life. My question is how do you decide on the powder load for fire forming: Two...

www.snipershide.com

Well, to be honest, you didn’t answer the question either. How exactly should one answer that particular question if one doesn’t push the brass to max speeds and pressures?

I know that personally, I’m not looking for a magic number if reloads for my brass. Admittedly, I’m not pushing Max speeds either. I find where there spear to be nodes and where I start seeing pressure signs and then back down one node to a speed that my barrel likes. I also get really good barrel life this way.

I’ll have to read what some do that like to push to the ragged edge. It’s no problem for me how you choose to use your expendables.

I didn’t try to answer it, elected not to attempt to educate out of my own ignorance.

But since you mention actually answering the OP’s question, here you go, OP, a thread on AccurateShooter.com to get you started. When I hear about people measuring web expansion, I always think about benchresters, they care about tiny measurements a bit more than the average Hide rat.

You are being redirected...

 

[ma smith]

Ask guys first, who has 10 firings on a magnum brass?

Then ask if that is reasonable to expect with other loads in other brass.

Only then would i worry about details. But at that stage at least you know who you are talking too...

Good luck

 

[spife7980]

My general rule of thumb, if you can feel the primary extraction ramp doing anything to pull the case out then you have too much pressure. Only high pressures should wedge a case into the chamber (provided your brass and chamber measurements jive).

 

[lash]

Ask guys first, who has 10 firings on a magnum brass?

Then ask if that is reasonable to expect with other loads in other brass.

Only then would i worry about details. But at that stage at least you know who you are talking too...

Good luck

I have well over 10 loadings on my .338 LM Lapua brass. I am pushing a 256gr solid at a modest 2950 fps. But I’m not maximizing pressure even with this load, so still cannot answer his question.

 

[Dead Eye Dick]

The best non answer answer is to consult a ouija board. Too many variables and the testing required goes beyond practical.

The test. Buy brass. Began ladder loading, staying well below maximum. Keep the brass from each ladder separate. Repeat firing the brass until each successive ladder shows a preponderance of loose primers. It would not hurt to anneal after each shooting. Maintain same lot numbers of bullets, brass, powder and primers. For the results to be valid,each part of the test, including shooting temperature, barrel temps, humidity must be the identical. That way, you will be able to determine if the longevity of the lot of brass that was tested.

The testing is part of a process called scientific method. Short version,

Scienrific Method, something in very, very short supply in the United States these days (Negative reference not intended to reference the OP)

The test above is frankly not practical, but shooting mild loads and not worrying is the true answer. In the end brass is still relatively cheap. (compared to an extensive test that may not be valid for successive issues of brass).

 

[Mike Casselton]

It's all pretty easy actually.

If you're shooting a 6.5 CM and you want to try and get 6.5 PRC velocities, get a 6.5 PRC.

Everyone tries to hot rod their rifle. They think they can find some special thing that only they do to get another 200fps.

It doesn't work.

We're all guilty of wanting more, but there isn't a magic button to getting more performance.

I know you're asking about the 300 WSM.
With the cost of brass, I'd want as many loadings as I could get too.
The answer is easy. Stay within the confines of the loading manuals and you'll usually get plenty of firings from your brass.

Live with its limitations or change to the 300 PRC or the Norma for more performance.

 

[clcustom1911]

I realize that new brass benefits from fireforming to your chamber, using a medium load that does not blow out the primer pocket on the first firing. The first firing hardens the case head and buys you longer brass life.

My question is how do you decide on the powder load for fire forming: Two grains above book minimum or two of three grains below book max?

I use my normal loading. When switching brass brands I weigh the casing after sizing to the same dimensions as my regular brass. If the new brass is heavier with the same dimensions, it obviously has less internal volume. Per 10 grains of brass weight, it's a 1 grain charge weight difference for me. So, for example:

With Hornady large primer brass weighing 155gr, I use 41.5 grains of H4350 under a 142 Matchking.

With Prime large primer brass weighing 160gr, I use 41gr of H4350 under the same bullet.

I've done this change ratio several times and it's panned out fairly well.

Also: Do you guys measure the expansion in the web diameter, using a micrometer that can read accurately down to 0.1 thou? Measure before you FL resize or after? That seems to change the measurement by 1-1.5 thou.

I don't measure with micrometer. I use a chamber check gauge as a go/no-go.

How much web expansion do you expect to see on the first firing, and how much on subsequent firings? What is too much?

If it still fits in a chamber check gauge, and primers are tight to get in, you're good. If a primer just glides out/in with no resistance, or doesn't fit in chamber check gauge after sizing, I toss the brass.

One trick i read about is to take a set of pre-weighed containers of powder to the range, say 2.0 grains apart (like 64.0, 66.0, 68.0 gn), starting middle of range, and sacrifice one case by loading it with successively higher powder loads at the range until the primer falls out. Presumably using a neck sizer and an arbor press. Has anybody tried that?

Sounds unsafe and pointless since your sample size is 1 piece. The amount of data gathered from testing 1 casing means exactly nada in the grand schemeof things. You would need to have/test at least 30 pieces of brass that are all close to the EXACT same dimensions (weight and thickness in all areas consistent from case to case) to get any data of true statistical validity.

It's like saying you can have the extreme spread, standard deviation, average velocity and hit probabability from firing only 1 round.... Yeah...no.

For PRS level accuracy you're maybe getting a bit too far into the weeds. It's easy to do because there's a rough estimation of somewhere between 0 and 4,023 variables to consider when thinking of different combinations of shooter/rifle/components/purpose/weather/press/dies/scale/safety.

 

[Dead Eye Dick]

It's all pretty easy actually.

If you're shooting a 6.5 CM and you want to try and get 6.5 PRC velocities, get a 6.5 PRC.

Everyone tries to hot rod their rifle. They think they can find some special thing that only they do to get another 200fps.

It doesn't work.

We're all guilty of wanting more, but there isn't a magic button to getting more performance.

I know you're asking about the 300 WSM.
With the cost of brass, I'd want as many loadings as I could get too.
The answer is easy. Stay within the confines of the loading manuals and you'll usually get plenty of firings from your brass.

Live with its limitations or change to the 300 PRC or the Norma for more performance.

You hit the nail on the head brother. As I always say, if you want more power, get a bigger rifle.

 

[NamibHunter]

Thanks for all the replies, much appreciated!

Maybe just a bit of additional context: I am trying to learn ELR, but no funds for a new 375 or a 416 rifle. Want to build a Long Range rifle on a budget. It will probably not be competitive in ELR events (not enough splash from a medium weight bullet), but hope to get enough gun to shoot at 2,000 yard steel targets and learn the game. i do realize this is going to be rather difficult.

So: I am restricted to using an existing short action Curtis Axiom action i already own. [Kids-in-college situation means i have to cut back on my shooting expenditures.]. The concept i am trying to make work here is to shoot the largest cartridge i can fit into a short action (therefore 300 WSM, around 75 grains of water capacity), single feed so i can ignore mag length restrictions, use a longer barrel (28”), and use the PVA Seneca 241 grain solid copper projectile with a claimed G1 BC over 1. G7 at 2,800 fps is listed as 0.555. This is approaching 375 territory. I won’t get to that speed, but hope to get the G7 above 0.500 at 2,700 fps muzzle velocity. The Seneca is a bore rider design and initial testing has shown that clear pressure signs arrive late for such a heavy projectile. It is a 7 twist barrel. Freebore is short at 0.125” because the entire nose profile is below bore diameter. Very short full diameter bearing surface, which is above the neck-shoulder junction, and the boat tail does not intrude significantly into the powder column. So usable case capacity is about 70 grains of 4000MR (which is almost a ball powder, very tiny extruded granules). It meters like a ball powder, but i will weigh all charges on an FX120.

Load/book max data is not particularly useful here, because of the bullet design, also i am running 4000MR (what i could find so far) and there is very little load data for this fairly new powder (especially for heavy 30 cal projectiles). So uncharted territory.

Have been able to get to 2,770 fps when hard bolt life arrived, and a feint half moon ejector mark, but that particular Nosler case had a pretty loose primer pocket after that one firing. Still holding a primer, but i probably reduced the life of this particular case by 50% or more. Web diameter did go up, but the pin gauges i have says the primer pocket is still below max spec. Will try the ball bearing trick.

Will also redo the pressure test in smaller increments (0.3 grain) and look for a wide flat spot in the speed graph. If that is somewhere between 2,600 fps and 2,720 fps, i will probably optimize seating dept at that slow speed and live with the reduction in supersonic range.

 

[NamibHunter]

Your “trick” looks like a great way to push past safe pressure limits if your waiting for the primer to just fall out. Possibly resulting in catastrophic failure

Personally I take virgin brass, maybe run a mandrel through it. Then load it and find the best load the virgin brass shoots. Then shoot and practice with.

Once I get through the virgin brass or enough of it to test then I’ll retest. I let my rifle tell me what it wants to shoot. Some shoot better faster some slower.

If your looking for long range performance then velocity and BC are your friends. Chasing higher velocity generally results in higher pressure and less case life. Some case like hornady or federal tend to give out before quality brass like Lapua

Just play within the limits and watch for pressure signs when creeping up the powder charge.

Brass is like barrels. If you want performance you’ll likely sacrifice life

So buy more brass when needed

If your truly concerned about brass life then two steps will help you

1) Load on the lowest node. If the rifle shoots good at 2650 FPS and 2850 FPS the 2650 will likely result in better brass life. With long range performance as a trade off

2) The second way to conserve brass……Don’t shoot……

Agree “the trick” is probably unsafe, unless you move up in smaller increments (maybe 0.3 or 0.4 grains), and take a set of 0.210”/0.211” gauge pins to the range - and stop well before primers actually fall out.

Made an edit to protect the unwary.

 

[NamibHunter]

unless you over clean a primer pocket and remove too much metal , there are ways to tighten them back a bit


unless you see case head separation , I don't worry about my brass so much . I have 6k pieces of factory hornady some that I have shot 6x's , and cross my fingers no problems so far so good . treat it like gold but enjoy it .

Primer pockets were left intact and unmolested. The virgin brass was well below minimum primer pocket spec, have expanded probably about 1.0 to 1.5 thou.

My 0.209” go-gauge goes halfway into the primer pocket, so probably still at 0.2085”.

 

[chase723]

Norma and RCC brass will likely get you there.

Norma Brass - .300 WSM (Qty 100) - Bullet Central

Norma Brass – .300 WSM (Qty 100)

www.bulletcentral.com

You could also just buy more brass (I.e. 200 pieces instead of 100 pieces or whatever) and so by the time you burn out your barrel your brass will have 1/2 the number of firings on it.

 

[Dead Eye Dick]

My suggestion.

Start saving for a long action rifle. An RPR or several others are not bank breakers and after a few months putting back money each month, one could show up at your door.

Continue shooting at targets half the size or smaller than you are shooting at now, at the ranges your rifle is comfortable with reasonable loads. This is the same process folks who practice big bore PRS with small bore / rimfire PRS.

Frankly, its not worth pushing your rifle to its limits if you are stressed for cash. In fact it might be be the worst thing.

 

[NamibHunter]

Duplicate removed.

 

[NamibHunter]

I didn’t try to answer it, elected not to attempt to educate out of my own ignorance.

But since you mention actually answering the OP’s question, here you go, OP, a thread on AccurateShooter.com to get you started. When I hear about people measuring web expansion, I always think about benchresters, they care about tiny measurements a bit more than the average Hide rat.

You are being redirected...

Thanks for the link, that provided the answer i was looking for (sort of). According to the quoted text, normal magnum case head expansion per shot is between 0.6 and 0.7 thou (0.0006” to 0.0007”). But depends on brass hardness/quality. [So a Lapua case will expand less than a Winchester case, at the same pressure.]

Other sources indicated that the first firing can produce double that expansion, and that expansion settles down to 0.5 thou expansion after 2-3 firings, if you avoid over pressure situations. The web expansion on the first firing (even at acceptable chamber pressure) work hardens the brass, which slows down further expansion. Which means it makes sense to use a middle-of-the-range load for the fire forming process and pre-harden your case heads before you do any pressure testing or load development, to avoid excessive expansion on the first firing.

Copied the useful text from Hodgedons, and removed the stray formatting characters:

“Using a blade micrometer that measures in ten thousandths (0.0001"), new unfired cases can be gauged before and after firing to determine reasonably accurate maximum loads. Micrometers measuring in thousandths (0.001") are insufficiently accurate to perform these measurements, and should not be used. Previously fired cases cannot be used accurately due to various levels of brass hardening. Measurement is taken just ahead of the extractor groove on the case head and must be taken at the same place on the case before and after firing.

By placing a small mark on the case head before entering the cartridge in the chamber with mark at 12 o’clock, a consistently accurate measurement can be taken with each firing”. [NH: Seems to imply that web expansion depends a little bit on case orientation relative to the lugs), so orient the mark the same every time when you insert a case in the chamber, and measure only at the line, and at the same distance from the groove.]

“Lower pressure rounds, like the .30-30 Winchester, usually yield maximum pressures at 0.0003" to 0.0004" expansion. Modern cartridges, like the .223 Remington, will show maximum pressure at 0.0004" to 0.0005", while .308 Winchester, .270 Winchester, etc., typically yield 0.0005" to 0.0006" expansion at max pressure. Magnums, like the .300 Winchester Magnum, show maximums at 0.0006” to 0.0007” expansion, and should be measured on the belt.”

Question answered, thanks for helping out guys!

 

[Steel head]

I find my initial first firing load through experiments and past loading data or online data that seems reasonable
Usually it’s about 100-150 FPS below my final load.

Knowing that new barrels can speed up, I go easy till it happens and all of the lot of brass for that barrel is once fired.

My current normal loads in 260, 7 saum and 338 edge(265 solids) don’t wreck brass, my hot load with 285 solids for my 338 is hard on brass but I don’t care because I like the performance.

 

[NamibHunter]

It seems i was measuring the “web” diameter too far above the extraction groove (micrometer anvil is 0.25” wide), and it was picking up changes in body diameter.

I have 100 Norma cases and 50 Nosler. Weight varies a lot between Norma and Nosler, so unlikely they were made in the same factory. Divided the Norma brass into two batches of 40 each, plus 20 outliers/fouling rounds. Fairly narrow weight range (3.5 grain) per batch of 40.

We shall see which brand is best soon.

 

[NamibHunter]

I collect one case of each caliber i find on the concrete at the range. Just now deprimed all the magnum cases (6.5 SAUM, 270 WSM, 257 Weatherby Magnum, 7 Remington Magnum, 375 Ruger, 300 Winmag, 338LM, 338 Rem Ultramag, 375 H&H, and a 300-378 Weatherby), then measured primer pocket diameter with the pin gauges. All cases look like once fired factory ammo. All but one had enough primer pocket expansion to allow the go-pin to go in all the way. The 300-378 Weatherby was the only case that had a loose fit and the go-pin (0.209”) could wiggle, but not yet enough to allow the no-go (0.211”) pin to go in more than 1/5 of the way. All my 300 WSM brass (most are at now 3x fired) does not allow the go-pin to enter more than 1/4 way. So i guess my 300 WSM loads were all below factory pressures?

My suspicion is that i was seeing false pressure signs, and that i was not measuring web expansion in the correct place, seeing numbers which were 1.5 thou higher than actual reality.

Also had a small but sharp burr on the new magnum bolt (ejector pin hole was not properly cleaned up), and seeing bright ejector marks plus bolt swipe well below book minimum. Already had that taken care of. No ejector marks anymore at fire forming pressures.

I think i will have to redo my pressure test.

 

[NamibHunter]

Redid pressure test and hit definitive pressure signs at 2,770 fps with the 241 Seneca bullet loaded to a 20 thou jump using 4000MR powder (not ideal, just cannot find N570): Hard bolt lift, primer crater gets pronounced and a full moon ejector mark, and primer pocket opened up 2 thou in one shot (via pin gauges).

So i need to back off at least 1.5 to 2.0 grains from there, leaving me at 2,630 fps. At that speed the primer pockets and web expansion were all minimal, around 0.4 thou.

A combo of not enough case volume, not the ideal powder for this class of bullet, and rather soft brass. Will try the 212 Seneca next.

Btw when measured in the correct spot, primer pocket enlargement does correlate fairly well with case web expansion. Just keep the two anvils of the micrometer far away from the case body, which expands another 1.5 thou, but the FL die will push that back in again. [Yes - doing this means you are well into the weeds, and this is certainly not required for practical reloading, but just for the sake of interest.]

The top three cases all went from a happy state where the 0.209” pin will not go into the primer pocket even 10%, to full insertion is possible but requiring some force (cases are still usable, but have lost a lof of life). The top load at 2,770 fps had expanded the primer pocket enough for the 209 pin to wiggle freely. Very very easy to seat a primer now, and maybe 1 or 2 more reloads before the ball bearing trick will have to be used.

 

[NamibHunter]

Situation prior to latest pressure test: “Go-Pin” will not go in at all.

Useful little tool.

 

[Steel head]

Redid pressure test and hit definitive pressure signs at 2,770 fps with the 241 Seneca bullet loaded to a 20 thou jump using 4000MR powder (not ideal, just cannot find N570): Hard bolt lift, primer crater gets pronounced and a full moon ejector mark, and primer pocket opened up 2 thou in one shot (via pin gauges).

So i need to back off at least 1.5 to 2.0 grains from there, leaving me at 2,630 fps. At that speed the primer pockets and web expansion were all minimal, around 0.4 thou.

A combo of not enough case volume, not the ideal powder for this class of bullet, and rather soft brass. Will try the 212 Seneca next.

Btw if measured in the correct spot, primer pocket movement does correlate well with web expansion. Just stay far away from the case body. [Yes doing this means you are well into the weeds, and this is certainly not required for practical reloading, but just for the same of interest.]

The top three cases all went from a happy state where the 0.209” pin will not go into the primer pocket even 10%, to full insertion is possible but requiring some force (cases are still usable, but have lost a lof of life). The top load at 2,770 fps had expanded the primer pocket enough for the 209 pin to wiggle freely. Very very easy to seat a primer now, and maybe 1 or 2 more reloads before the ball bearing trick will have to be used.

Yea
I think you’ll be getting better results with the 212 or even 198 solids.
Really need 85-100 grains of powder to get those 241’s up to speed.

I do think that 300WSM should be pretty interesting with the lighter solids.

 

[NamibHunter]

Yea
I think you’ll be getting better results with the 212 or even 198 solids.
Really need 85-100 grains of powder to get those 241’s up to speed.

I do think that 300WSM should be pretty interesting with the lighter solids.

Supersonic range only reduces by 150 yards or so going from 241 gn Seneca at 2,630 fps compared to 212 gn at 2,900 fps (Hornady book data plus 100 fps for additional 4” of barrel).

A 2,000 yard supersonic range at sea level is still very much acceptable. For a short action 30 caliber. By comparison, a 338LM pushing the 300 Atip at 2,750 fps will do 1,750 yards.

 

[Steel head]

Supersonic range only reduces by 150 yards or so going from 241 gn Seneca at 2,630 fps compared to 212 gn at 2,900 fps (Hornady book data plus 100 fps for additional 4” of barrel).

A 2,000 yard supersonic range at sea level is still very much acceptable. For a short action 30 caliber. By comparison, a 338LM pushing the 300 Atip at 2,750 fps will do 1,750 yards.

Puny, weak lapua!

 

[KnowNothing256]

Supersonic range only reduces by 150 yards or so going from 241 gn Seneca at 2,630 fps compared to 212 gn at 2,900 fps (Hornady book data plus 100 fps for additional 4” of barrel).

A 2,000 yard supersonic range at sea level is still very much acceptable. For a short action 30 caliber. By comparison, a 338LM pushing the 300 Atip at 2,750 fps will do 1,750 yards.

Why give up supersonic range? If the 241’s are outreaching the lighter bullets, even when loaded to lower pressure/speed, what’s the advantage in the light bullet?

 

[NamibHunter]

Managed to buy 100 pieces of ADG 300 WSM brass yesterday, out of stock already. Apparently the heads are stamped twice to make it 5-10% harder than Lapua brass.

Should allow me to get to the higher node, similar to the 300 SAUM.

 

[Steel head]

Managed to buy 100 pieces of ADG 300 WSM brass yesterday, out of stock already. Apparently the heads are stamped twice to make it 5-10% harder than Lapua brass.

Should allow me to get to the higher node, similar to the 300 SAUM.

I’m sure the f class guys bought a shit ton of it.

If you ever get the chance measure the usable capacity for it.

 

[NamibHunter]

I’m sure the f class guys bought a shit ton of it.

If you ever get the chance measure the usable capacity for it.

Sure, will compare weight, neck thickness, and internal volume, for Norma, ADG, and brand new Nosler (apparently, it is not rebranded Norma anymore - allegedly!).

Will also see how much difference in speed i get for the same (safe) load between the different brands of brass.

 

[secondofangle2]

do load development with the same 10-20 cases reloaded over and over and that will tell you sooner whether you're loading too hot.

 

[Steel head]

Sure, will compare weight, neck thickness, and internal volume, for Norma, ADG, and brand new Nosler (apparently, it is not rebranded Norma anymore - allegedly!).

Will also see how much difference in speed i get for the same (safe) load between the different brands of brass.

Seat a bullet at normal position put water up the the flash hole and get water volume to get a nice measurement of usable case capacity.

 

[NamibHunter]

Seat a bullet at normal position put water up the the flash hole and get water volume to get a nice measurement of usable case capacity.

Based on the 100 cases of ADG 300 WSM brass i recently got (2 boxes, same serial nr and Lot nr):

Weight range:

Low: 232.4 gn
High: 234.62 gn
Average: About 233.5 gn

Water capacity (to top of neck, plug with O-ring in the primer pocket): 81.2 gn for the heaviest two cases. Lightest cases should be just below 82 grains.

Could not determine “usable case capacity” with bullet correctly seated in a dummy round: You really need a syringe and a thin needle to pump the water into the case via the flash hole, dunking the dummy round under water does not work, air bubbles obstruct water flow. [I did not want to drill a larger hole in the primer pocket…]

Brass did not show pressure signs at my previous max load developed using Norma brass, which topped out at 2770 fps using a 225 ELDM and 4000 MR powder (hard bolt lift). Got to 2840 fps with the heaviest 10 pieces of ADG brass in my batch, in a 30” 8 twist MPA barrel, and bolt lift was still ok. Primers had good radius, almost no cratering, and no ejector stamp marks. Should be able to go up some more.

Reason is presumably two-fold: ADG brass has more case volume, and ADG case heads are harder than alternatives, resisting “stamping” by the ejector hole.

Norma brass is significantly heavier, and had a slightly wider weight range: Varied from 245 to 247.5 gn. I chose to divide the Norma batch into two smaller batches of 40 each, and around 10 outliers were put aside for experimenting.

Early days - but so far, the newly released ADG brass for the 300 “Wism” has impressed me. Might get me to the higher node while preserving brass life.

Starting to understand why folks say that if premium brass is NOT available for a chambering you are considering, it is best avoided until either Lapua, ADG, Alpha or Peterson steps up.

 

[NamibHunter]

OK, eventually found a post elsewhere that explained how to “scientifically” find the max load where primer pockets will deliver a specified nr of reloads:

Sort your two boxes of precious ADG brass (the first premium brass ever manufactured for 300 WSM) into two batches of 40-50 each. Keep the 10 worst brass on the heavy side in a “rejects” pile. [ADG brass had such a narrow weight range that it is blasphemy to call these 10 cases “rejects”. They were just 1.5 grain heavier than average. For typical brass that helps to get ris of the “long tail” in the statistical distribution.]

Do all pressure testing on those 10 heavy cases. No damage done to your two primary batches. Also by using the heaviest 10 cases, you have some added safety margin when loading your primary cases with slightly lower weight, and about 1% more case volume.

Serialize the 10 cases, so they have numbers. Idea is same load goes in the same case to determine when the primer pocket becomes unusable.

Fire form the 10 cases with a medium load about 3 grains below book max. This typically produces the biggest increase in primer pocket diameter, about 0.5-0.6 thou. It settles down from the second firing.

Measure primer pocket inside diamter with a micrometer and record the numbers noting serial nr. [This is hard to do accurately.]

Run the first pressure test in 1.0 grain increments (1.0 for a magnum case, 0.5 for a 308 size case), until the first MILD pressure sites show up. Now load 1 and 2 grains higher (for a magnum) and repeat, carefully. If true hard bolt lift or significant pressure signs (shiny full moon ejector mark) show up, stop and pull the remaining bullets, and reset max load as required.

To save on components: Repeat only on the top three cases that you know are within safe max pressure. Fire each case 5 times, with the same load in the same numbered case. Measure primer pocket expansion and case head expansion after 5 firings. Calculate average expansion per full load firing (ignore the fire forming step).

This approach overcomes the problems with measurement errors: An inside mic requires very consistent “feel” from you and errors as large as 0.3 thou are entirely possible. Getting an average expansion over 5 reloads mitigates this problems.

Also, only two or three cases are sacrificed in the process. Keep remaining (heavy) brass for future pressure testing when trying out other bullets or powders.

My results were: Fire forming with a load 200 fps slower than book max expanded the pocket 0.5 to 0.6 thou on average. This is typical. Subsequent firings gave 0.25 to 0.35 thou per firing, on average, depending on load.

With a 30” MPA/Spencer barrel, HBN coated 225 ELDM, very long freebore, and using 4000MR (known for achieving the same high speed as RL-26), i could get to 2925 fps before hard bolt lift and a feint full moon primer stamp arrived. I stopped there, even though another 1 grain might have been possible. No reason to be unsafe.

Over four firings, i got primer pocket expansion of 0.35 thou per firing on the top pressure round, and about 0.25 thou/firing 2 grains lower. Virgin ADG primer pocket measured 0.2085” thou on arrival. After fire forming, they were at 0.2898 to 0.2090” (so 0.5 thou expansion).

My no-go gauge measures 0.2108”, or almost 0.211”. Let’s assume primers will fall out at that point (0.211”). That gives me 2.0 thou of room to use up over multiple firings, so about 6 reloads on the top round (medium hard bolt lift), which is not enough. Case exposed to the second highest load would give me about 9 reloads, better but not quite enough. The third highest case was projected/calculated to gave 11-12 reloads, which is OK. This is also the load that gives just a hint of pressure (slight increase in bolt lift force needed, tiny ejector mark, minimal primer crater). [Other case had progressively more soot on the shoulder, indicating pressure was too low.]

So yes there is a scientific method that is safe and not overly expensive on components or barrel life. But it means full length sizing at the range and reloading from small bottles of powder measured out before.

BUT in the case of premium brass, all you really need to do is look for the first pressure signs and stop there.

For weak-in-the-head brass like Nosler, this rule does not work! Norma was better, but not quote premium quality.

 

[918v]

Lol that’s insane

 

[secondofangle2]

Yeah, I'd either load them safe so pocket expansion is not an issue or say "I give no fucks" and run them hot if speed were that important to me.

 

[NamibHunter]

A long winded way to say “keep it simple stupid”:

1) Buy only premium brass. If Lapua, ADG, Alpha or Peterson does not make brass for the caliber you are interested in, it is best to avoid it until such time as one of them steps up. Took a year to get my hands on ADG brass. Will be another year before they make it again! Mad scramble every time to get the order in.

2) Life is too short to be dealing with low quality brass!

 

[NamibHunter]

 

[Steel head]

View attachment 7820532

View attachment 7820533

That was my first press

 

[918v]

View attachment 7820532

View attachment 7820533

That press is made out of cast aluminum not iron.

 

[NamibHunter]

Update of ADG brass life after about 7 reloads:

ADG brass allows me to run about 120 fps more, for the Hornady 225 ELDM. I get 2890 fps instead of the prior 2770 (for the old Norma brass) before a medium hard bolt lift shows up. Now running the 225’s at 2850, where i found a nice wide node with an SD of 4.7 fps (for 25 shots). One reason is that ADG has more case capacity. Also the heads are harder. But this is from a 30” barrel, long throated, and these are HBN coated bullets.

ADG case head is very hard, and primer pockets stand up well to the fairly high pressure rounds that leave faint ejector marks, around 1.5 grain below the point where shiny full moon circles show up. I check them with a go and no-go gauge every time. Have 7 reloads on them so far, and still doing very well. Expect 5-7 more reloads, but we shall see.

In general, for all calibers, i highly recommend ADG brass: On par with with Lapua and Alpha (who so far refuse to make 300 WSM bras). Far better than Norma, and way way better than Hornady.

 

[TripleBull]

The best non answer answer is to consult a ouija board. Too many variables and the testing required goes beyond practical.

The test. Buy brass. Began ladder loading, staying well below maximum. Keep the brass from each ladder separate. Repeat firing the brass until each successive ladder shows a preponderance of loose primers. It would not hurt to anneal after each shooting. Maintain same lot numbers of bullets, brass, powder and primers. For the results to be valid,each part of the test, including shooting temperature, barrel temps, humidity must be the identical. That way, you will be able to determine if the longevity of the lot of brass that was tested.

The testing is part of a process called scientific method. Short version, View attachment 7778145
Scienrific Method, something in very, very short supply in the United States these days (Negative reference not intended to reference the OP)

The test above is frankly not practical, but shooting mild loads and not worrying is the true answer. In the end brass is still relatively cheap. (compared to an extensive test that may not be valid for successive issues of brass).

This thread was fun to read through. I feel like I'm hanging out with some potential benchrest candidates, most of which aren't going to be able to reach the minimum OCD level required for a full-on benchrest infection.

WRT scientific method, the diagram you gave is part of the process. The history of scientific method (SM) is fascinating to a nerd like me. Many people credit Francis Bacon as the key developer of SM and you can find all kinds of support for that point of view:

Baconian method | Inductive reasoning, Scientific method, Empiricism | Britannica

Baconian method, methodical observation of facts as a means of studying and interpreting natural phenomena. This essentially empirical method was formulated early in the 17th century by Francis Bacon, an English philosopher, as a scientific substitute for the prevailing systems of thought, which,

www.britannica.com

In fact, the foundations of SM (not S&M, you pervert) date back at least as far as the life of Ibn Al Hytham (965-1040AD). Some people consider him to be the first scientist:

BBC NEWS | Science & Environment | The 'first true scientist'

news.bbc.co.uk

A dude named Jim Al-Khalili wrote a book titled "The House of Wisdom" that is an excellent read on the history of Arabic science. Chapter 11 is titled "The Physicist" and it centers on the work of Al Hytham. The chapter opens with a quote written by Al Hytham about peer review in science that, way the fuck back there around 1000 AD, reveals the fundamental, philosophical core of the scientific method, which is to find ways to keep preconceived notions and biases from resulting in acceptance of the wrong hypothesis:

"The seeker after truth is not one who studies the writings of the ancients and, following his natural disposition, puts his trust in them, but rather the one that suspects his faith in them, and questions what he gathers from them, the one who submits to argument and demonstration and not the sayings of human beings whose nature is fraught with all kinds of imperfection and deficiency. Thus, the duty of the man who investigates the writings of scientists, if learning the truth is the goal, is to make himself an enemy of all that he reads, and, applying his mind to the core and margins of its content, attack it from every side. He should also suspect himself as he performs his critical examination of it, so that he may avoid falling into either prejudice or leniency."

Bold added by me - I'm not sure they even had bold font back in AD1000 and the above demonstrates that those pontificating motherfuckers didn't teach how to avoid run-on sentences and if I work at it hard enough, can show that some of us don't avoid them very well either, while preaching from a creaky crate in the middle of the Hide town square reloading forum. The point I'm making is that, if one wants the scientific method to work , first we must doubt what we believe to be true. We have to be our own harshest critic, so our peer reviewers can dig deeper after we already dug a pretty deep hole of self-doubt.

 

[NamibHunter]

Update: Now on reload nr 10 and the ADG brass is holding up very well. Primer pockets are still tight, and the inside micrometer (hard to use device, so accuracy is not stellar) as well as the pin gauges (accurate) says that most of the pockets have opened up from 0.2081” to 0.2106”, or 2.5 thou of expansion, or 0.25 thou per shot on average. Around 0.2115” the pockets will not hold a CCI 250 primer anymore. So maybe 30% of life left in them, pointing at possibly 15-16 reloads. Ran the first 5 shots at the lower node (50 - 60 fps slower), and that probably also helped to prolong case life.

Also: Managed to get the 225 ELDM to a reliable 2850 fps from the rather long 30” 8 twist barrel, with no pressure signs. I realize that's high for a 225 bullet from a 300 WSM rifle. Several mods were used to gain maximum safe speed: HBN coated bullets, long barrel, very long freebore, and using ADG brass, which has more case capacity, because it is not as thick as the Norma WSM brass (rather soft). This load is about 50 fps below the point where a medium hard bolt lift shows up.

Very happy with the performance of this short action MPA switch barrel rifle.

 

[NamibHunter]

In short, if you can find ADG brass in 300 WSM, buy as much as they will let you. Currently sold out everywhere. Next production run is apparently end of 2022.

The best i could get from the Norma brass was 2785 fps. Too thick (so reduced case capacity), and a little soft.

ADG is giving Lapua a run for their money.

 

[semperfireloading]

This is a funny thread. Silly. The answer has been around over 400 years. Its called the scientific method. So let me tell you what that means is simple terms, applied to your brass life.

Make set of brass, same type of brass, same everything.
Measure primer pockets and brass size before shooting
Shoot lots of different powder charges
measure everything, document.
do it again, and again, and again, until you see the lots failing
repeat it to make sure you get same results

You will notice, that the scientific method, will automatically steer you to what works, and what doesn't.

You don't need anyone to tell you all that, its common sense.

Another way to look at this, is what is called the "Deming Cycle", which is basically simplified scientific method applied to manufacturing.

Make a plan
set a goal (do
Check it
countermeasure (actions)

until you get what you want.

 

[lash]

This is a funny thread. Silly. The answer has been around over 400 years. Its called the scientific method. So let me tell you what that means is simple terms, applied to your brass life.

Make set of brass, same type of brass, same everything.
Measure primer pockets and brass size before shooting
Shoot lots of different powder charges
measure everything, document.
do it again, and again, and again, until you see the lots failing
repeat it to make sure you get same results

You will notice, that the scientific method, will automatically steer you to what works, and what doesn't.

You don't need anyone to tell you all that, its common sense.

Another way to look at this, is what is called the "Deming Cycle", which is basically simplified scientific method applied to manufacturing.

Make a plan
set a goal (do
Check it
countermeasure (actions)

until you get what you want.

You forgot to finish your method with, “Replace barrel. Start over.”

 

[918v]

I have found that sticking to book loads tends to prolong brass life. Doing stupid shit tends to reduce brass life. It’s not just primer pockets that fails. Case head separation tends to come around sooner with hot loads.

Stupid shit includes but is not limited to:

doing anything that causes pressure signs… achieving higher velocities than everyone else… loading 2grs over max… etc.

 

[Average guy]

Agreed 100 percent. My last 6 creedmoor barrel went 1700 accurate rounds, all on 100 pieces of brass. I could have stood on the gas a lot more, but why. 100 fps more would have done anything for me.