ES too high

[markl323]

Some updates from last weekend's testing. All case mouths were chamfered inside and outside before being run through the mandrel.

- 5 x 5-shot groups with 43gr. 1x fired brass. Brass not cleaned. Average ES is 20 which is a significant improvement from the usual 25-30 average ES of fire formed brass. Highest ES is 33 the rest was 22 and below. As mentioned before, I typically could only get an average ES of 20 with virgin brass.

- 9 x 5-shot groups with 41.8 gr. Virgin brass. Average ES is 21 which is slightly worse than usual. I used to load at 41.8 gr but I moved to 43 gr hoping to get rid of these groups with high ES/SD.

 

[FredHammer]

True, but you don’t need to lube anything if you chamfer after, last brass prep step before you seat bullets…

The last thing going through the necks is my mandrel with imperial size wax applied. It smooths the rough chamfer surface. (Lube removed from necks with alcohol swab prior to bullet seating) The bullets have nice smooth seating. Didn't with the rough surface of the chamfer. It's just a little technique I found to work for my process. Thought I'd share.

 

[straightshooter1]

Some updates from last weekend's testing. All case mouths were chamfered inside and outside before being run through the mandrel.

- 5 x 5-shot groups with 43gr. 1x fired brass. Brass not cleaned. Average ES is 20 which is a significant improvement from the usual 25-30 average ES of fire formed brass. Highest ES is 33 the rest was 22 and below. As mentioned before, I typically could only get an average ES of 20 with virgin brass.

- 9 x 5-shot groups with 41.8 gr. Virgin brass. Average ES is 21 which is slightly worse than usual. I used to load at 41.8 gr but I moved to 43 gr hoping to get rid of these groups with high ES/SD.

Was the chamfering the only thing you did different?

What did you do about primer seating depth, if anything?

It's not out of the ordinary for ES to be around 30 or so when looking at a large number of firings. . . like >10 firings. When looking at 5 firings, I would expect the EX to be in the teens, even the low teens (if not better). Here's an example from some recent testing I've done (look at the columns at the right):

 

[FredHammer]

Some updates from last weekend's testing. All case mouths were chamfered inside and outside before being run through the mandrel.

- 5 x 5-shot groups with 43gr. 1x fired brass. Brass not cleaned. Average ES is 20 which is a significant improvement from the usual 25-30 average ES of fire formed brass. Highest ES is 33 the rest was 22 and below. As mentioned before, I typically could only get an average ES of 20 with virgin brass.

- 9 x 5-shot groups with 41.8 gr. Virgin brass. Average ES is 21 which is slightly worse than usual. I used to load at 41.8 gr but I moved to 43 gr hoping to get rid of these groups with high ES/SD.

Something to check also is the ambient temp vs loaded round temp. I started experimenting with matching my ammo temp to ambient temp (like no air conditioning effects lingering on the case/powder) by letting them sit outside for an hour or more before firing. The temp matching is making me reduce powder charges I thought were safe in heat, but they were still cold inside the case when fired in hot temps.

The various temps of non-acclimated rounds fired from begging to end of a shooting session would show higher ES between the batches.

 

[axarob44]

No it doesn’t.

So you're saying the pins that polish and remove the annealing line / discoloration on the outside don't do the same thing on the inside? My cases are always full of pins when I dump the whole thing out. My mandrel does not gall the inside of the neck like if I were to not tumble the cases. That's just my experience with the process.

 

[CK1.0]

The last thing going through the necks is my mandrel with imperial size wax applied. It smooths the rough chamfer surface. (Lube removed from necks with alcohol swab prior to bullet seating) The bullets have nice smooth seating. Didn't with the rough surface of the chamfer. It's just a little technique I found to work for my process. Thought I'd share.

That sounds like a lot of extra work, I’m not sure why your chamfering comes out rough, but it shouldn’t… weird.

Almost sounds like you’re using the wrong tool or something?

Once the case has a proper inside chamfer, subsequent loadings require only a quick touch up, the cases “whistle” on my tool with very little pressure and in less than “one Mississippi” per case. Barely any material is removed and that’s all it takes. FWIW I use a Hornady Case Prep Duo, but with a VLD chamfer head instead of the standard chamfer tool most come with, the regular chamfer heads are nearly useless with most modern long range projectiles and do more harm than good IMO since they make a sharp ledge.

 

[FNG1001]

Some updates from last weekend's testing. All case mouths were chamfered inside and outside before being run through the mandrel.

- 5 x 5-shot groups with 43gr. 1x fired brass. Brass not cleaned. Average ES is 20 which is a significant improvement from the usual 25-30 average ES of fire formed brass. Highest ES is 33 the rest was 22 and below. As mentioned before, I typically could only get an average ES of 20 with virgin brass.

- 9 x 5-shot groups with 41.8 gr. Virgin brass. Average ES is 21 which is slightly worse than usual. I used to load at 41.8 gr but I moved to 43 gr hoping to get rid of these groups with high ES/SD.

Are you saying that you shot 25 rounds of 43gr, and 45 of 41.8gr, but you recorded the average 5-shot ES for each power charge? Why not calculate the SD and ES for the complete 25 shots of 43gr and the complete 45 shots of 41.8gr?

You're losing a lot of resolution by doing what it sounds like you did.

 

[SharpShooterSER]

my process that gives me single digit sd/es.
lapua brass
deprime
flame anneal
neck size shoulder bump .002 Forster
21st cent. mandrel
wet tumble with ss pins in Frankford tumbler, Arf(LemonShine) and Fairy, about an hour
blow out with air, leave for few days to dry
prime to touch the bottom on Lee Classic Cast
powder charge with FX320i scale and Auto Thrower - all within 0.02gn
bullet seat and check cbto on all to be exactly the same (RCBS Match seater, Hornady gauge), oal varies
trim, chamfer and deburr on every 5th or 6th firing
inside of the necks are not that dry so no lube needed, and bullets seat quite nice (by feel)
paper shows good results too on short and medium distances (no way to try at 1000 meters now).

 

[straightshooter1]

So you're saying the pins that polish and remove the annealing line / discoloration on the outside don't do the same thing on the inside? My cases are always full of pins when I dump the whole thing out. My mandrel does not gall the inside of the neck like if I were to not tumble the cases. That's just my experience with the process.

He's wrong, unless he's thinking in terms of tumbling with no media. The SS pins or chips do clean the inside neck surface quite clean, in fact. . . . even inside the primer pockets to a good extent.

 

[markl323]

Was the chamfering the only thing you did different?

What did you do about primer seating depth, if anything?

It's not out of the ordinary for ES to be around 30 or so when looking at a large number of firings. . . like >10 firings. When looking at 5 firings, I would expect the EX to be in the teens, even the low teens (if not better). Here's an example from some recent testing I've done (look at the columns at the right):

View attachment 8222041

- for the first 5x 5-shot groups, in addition to chamfering the case mouths, I skipped wet-dry tumbling. These are the groups that had an improvement. For the next 10x 5-shot groups, in additional to chamfering the case mouths, I lowered the power charge. these groups did not show an improvement.

- I used the same seating depth that has been producing 1 hole groups (0.050" jump).

- I calculate ES and SD for each of those individual 5-shot groups. then take the average. so each should be in the teens like you said. but they aren't.

 

[markl323]

my process that gives me single digit sd/es.
lapua brass
deprime
flame anneal
neck size shoulder bump .002 Forster
21st cent. mandrel
wet tumble with ss pins in Frankford tumbler, Arf(LemonShine) and Fairy, about an hour
blow out with air, leave for few days to dry
prime to touch the bottom on Lee Classic Cast
powder charge with FX320i scale and Auto Thrower - all within 0.02gn
bullet seat and check cbto on all to be exactly the same (RCBS Match seater, Hornady gauge), oal varies
trim, chamfer and deburr on every 5th or 6th firing
inside of the necks are not that dry so no lube needed, and bullets seat quite nice (by feel)
paper shows good results too on short and medium distances (no way to try at 1000 meters now).

impressive. is that 6.5 CM?

 

[markl323]

Are you saying that you shot 25 rounds of 43gr, and 45 of 41.8gr, but you recorded the average 5-shot ES for each power charge? Why not calculate the SD and ES for the complete 25 shots of 43gr and the complete 45 shots of 41.8gr?

You're losing a lot of resolution by doing what it sounds like you did.

Yes I only measure ES & SD for each 5-shot groups. then take the average for the 41.8 gr groups and the average for the 43 gr groups. I know it's a weird way of doing it. But there are several reasons. Currently, ES and SD are high enough that even when calculated with only 5 shots, the problem is already showing. Many folks calculate their numbers based on groups of 3 and 5 and I want to compare my results to those. If I calculate them in groups of 25 or 45, the numbers will always be higher and I won't be able tell how am I doing vs others. Another is reason is that I also sort bullets and cases in groups of 5.

 

[straightshooter1]

Yes I only measure ES & SD for each 5-shot groups. then take the average for the 41.8 gr groups and the average for the 43 gr groups. I know it's a weird way of doing it. But there are several reasons. Currently, ES and SD are high enough that even when calculated with only 5 shots, the problem is already showing. Many folks calculate their numbers based on groups of 3 and 5 and I want to compare my results to those. If I calculate them in groups of 25 or 45, the numbers will always be higher and I won't be able tell how am I doing vs others. Another is reason is that I also sort bullets and cases in groups of 5.

Since this is really about internal ballistics, I really feel you should take a close look at what's going on with your ignition as that can easily should up as poor ES's and SD's if thing like powder measure is accurate and seating depths are consistent. Like, maybe the magnum primers are not the best choice to get those numbers down and you could still maintain good precision results on paper with a different primer. I still feel seating primers to flush, as you've stated, is the place to really examine closely.

Fore example, my CCI 450 primers measure .121" in height (+/- .0005). My Lapua brass's primer pocket depth measures .121 (+/- .005). If I seat the primers to flush, some of them will be barely touching and others will not, which would produce variation in ignition. To get the anvil seated properly into the cup of the primer, I need to seat them ~.002 below flush to insured consistent ignition. I have Peterson brass and the primer pockets are .129" deep. To put the 450's flush means I'd be .008 from the bottom of the pocket. That would be a big problem for consistent ignition.

I have no idea the depth of your Alpha SRP primer pockets. You should measure your pockets to see how your CCI 450 primers actually fit. Getting the primers seating correctly, you may be surprised how much that helps your ES's and SD's.

Just to give you some ideas how seating flush with variances in primers might fit, my CCI-400's measure .119 - .122 and most of the variation is due to how the anvil is fitted into the cup. My Federal 205M's measure .117 - .121.

 

[ifgator]

Change the firing pin spring. How old is it and how many rounds has it fired??? Saw a video by fclsss John if I remember correctly chased his ass all over the place and some wise soul told him to do this. Cheap fix maybe???

 

[markl323]

Since this is really about internal ballistics, I really feel you should take a close look at what's going on with your ignition as that can easily should up as poor ES's and SD's if thing like powder measure is accurate and seating depths are consistent. Like, maybe the magnum primers are not the best choice to get those numbers down and you could still maintain good precision results on paper with a different primer. I still feel seating primers to flush, as you've stated, is the place to really examine closely.

Fore example, my CCI 450 primers measure .121" in height (+/- .0005). My Lapua brass's primer pocket depth measures .121 (+/- .005). If I seat the primers to flush, some of them will be barely touching and others will not, which would produce variation in ignition. To get the anvil seated properly into the cup of the primer, I need to seat them ~.002 below flush to insured consistent ignition. I have Peterson brass and the primer pockets are .129" deep. To put the 450's flush means I'd be .008 from the bottom of the pocket. That would be a big problem for consistent ignition.

I have no idea the depth of your Alpha SRP primer pockets. You should measure your pockets to see how your CCI 450 primers actually fit. Getting the primers seating correctly, you may be surprised how much that helps your ES's and SD's.

Just to give you some ideas how seating flush with variances in primers might fit, my CCI-400's measure .119 - .122 and most of the variation is due to how the anvil is fitted into the cup. My Federal 205M's measure .117 - .121.

It would be really strange if the problem was variations in power charge since I use the FX 120i.

After sizing I always measure the should length of each case and group them according to length (they can be +/- 1/1000). Then account for the difference when I seat the bullet. For example, if the shoulder length is 1/1000 shorter than the "standard" length, I reduce the cartridge base to ogive length by the same amount to keep the jump the same.

Apparently I was incorrect when saying it was seated flush. I just made some measurements.

Alpha SRP (virgin) pocket depth: 0.1240 - 0.1245
CCI 450 height 0.1200 - 0.1205
So if seated flush, max gap would be 0.1245 - 0.1200 = 0.0045"

However, after taking apart the primer "pin" from the Lyman press, I see its diameter is small enough to go inside the primer pocket hole a bit. So apparently it pushes the primer further inside the pocket.
Pin length = 0.7375
Case length = 1.9100 (total length of case + pin = 2.6475")
When pin is inserted into primer pocket, total length is 2.6080". So the pin goes inside 0.0395 which is more than enough to account for the possible max gap of 0.0045" above.

 

[markl323]

Change the firing pin spring. How old is it and how many rounds has it fired??? Saw a video by fclsss John if I remember correctly chased his ass all over the place and some wise soul told him to do this. Cheap fix maybe???

it would be very strange. I bought it "brand new". demo unit from EuroOptics and the local gun store inspected the barrel and said it was brand new. about 1K rounds.

 

[SharpShooterSER]

impressive. is that 6.5 CM?

Thanks 6.5x47 Lapua

 

[John Glidewell]

Alpha SRP (virgin) pocket depth: 0.1240 - 0.1245

How are you measuring? I have an actual tool to measure pockets and all my Alpha old brass is +/- .001. .005 variance is huge.

 

[straightshooter1]

It would be really strange if the problem was variations in power charge since I use the FX 120i.

After sizing I always measure the should length of each case and group them according to length (they can be +/- 1/1000). Then account for the difference when I seat the bullet. For example, if the shoulder length is 1/1000 shorter than the "standard" length, I reduce the cartridge base to ogive length by the same amount to keep the jump the same.

Apparently I was incorrect when saying it was seated flush. I just made some measurements.

Alpha SRP (virgin) pocket depth: 0.1240 - 0.1245
CCI 450 height 0.1200 - 0.1205
So if seated flush, max gap would be 0.1245 - 0.1200 = 0.0045"

However, after taking apart the primer "pin" from the Lyman press, I see its diameter is small enough to go inside the primer pocket hole a bit. So apparently it pushes the primer further inside the pocket.
Pin length = 0.7375
Case length = 1.9100 (total length of case + pin = 2.6475")
When pin is inserted into primer pocket, total length is 2.6080". So the pin goes inside 0.0395 which is more than enough to account for the possible max gap of 0.0045" above.

Yeah, I really wasn't questioning your powder charges or seating depths as it seemed to me you have a good handle on that. I was trying to emphasize the importance the primer has for the ignition cycle that actually starts with how the firing pin strikes the primer.

Yes, the pins that seat primers can easily move into the appropriate primer pockets. Most reloaders simply go by feel as to whether the primer is being seated below flush enough that it's against the bottom of the pockets. But to really know how far that is, measurement need to be made. One can simply use a good caliper to take a measurement after seating, though it takes a little practice to get it right for a relatively accurate reading.

So, you're not "seating flush" and seem to be saying that you're below flush. Have you measured how far below flush you really are?

Primer Seating Depth Uniformity and Accuracy « Daily Bulletin

USAMU shows how to measure primer seating depth for precision reloading. High primers can cause feeding problems or dangerous slam fires.

bulletin.accurateshooter.com

 

[markl323]

Yeah, I really wasn't questioning your powder charges or seating depths as it seemed to me you have a good handle on that. I was trying to emphasize the importance the primer has for the ignition cycle that actually starts with how the firing pin strikes the primer.

Yes, the pins that seat primers can easily move into the appropriate primer pockets. Most reloaders simply go by feel as to whether the primer is being seated below flush enough that it's against the bottom of the pockets. But to really know how far that is, measurement need to be made. One can simply use a good caliper to take a measurement after seating, though it takes a little practice to get it right for a relatively accurate reading.

So, you're not "seating flush" and seem to be saying that you're below flush. Have you measured how far below flush you really are?

Primer Seating Depth Uniformity and Accuracy « Daily Bulletin

USAMU shows how to measure primer seating depth for precision reloading. High primers can cause feeding problems or dangerous slam fires.

bulletin.accurateshooter.com

good call. I just seated one, the same way I have always done it.

• Alpha SPR (fired 1x) pocket depth 0.1235
• CCI 450 height 0.1200
• After seated, 0.0035 below flush

Looks about right. Although it possible that I sometimes didn't push the primer all the way in when I seated them. I'll measure from now on after seating.

 

[markl323]

How are you measuring? I have an actual tool to measure pockets and all my Alpha old brass is +/- .001. .005 variance is huge.

that's 0.0005.

 

[John Glidewell]

that's 0.0005.

Thanks, I miss read that. On your seating you can go farther. The measurements you posted the primer is barely bottoming in pocket. I go .002 crush on primers. And that is what primer manufacturers recommend. It will ensure a consistent ignition.

 

[markl323]

Thanks, I miss read that. On your seating you can go farther. The measurements you posted the primer is barely bottoming in pocket. I go .002 crush on primers. And that is what primer manufacturers recommend. It will ensure a consistent ignition.

ok now I know what that meant. (someone mentioned it a few days ago). how do you do that? I have pressed it as hard as I could.

 

[John Glidewell]

I use a bench mounted competition primer seater that adjusts .001 per click. The Frankford arsenal platinum primer seater is a decent entry level adjustable hand seater for the $$. I used one for a couple years. There are many others, it all comes down to how much $$ you want to spend. But you need an adjustable primer seater.

 

[FredHammer]

That sounds like a lot of extra work, I’m not sure why your chamfering comes out rough, but it shouldn’t… weird.

Almost sounds like you’re using the wrong tool or something?

Once the case has a proper inside chamfer, subsequent loadings require only a quick touch up, the cases “whistle” on my tool with very little pressure and in less than “one Mississippi” per case. Barely any material is removed and that’s all it takes. FWIW I use a Hornady Case Prep Duo, but with a VLD chamfer head instead of the standard chamfer tool most come with, the regular chamfer heads are nearly useless with most modern long range projectiles and do more harm than good IMO since they make a sharp ledge.

I'm not doing anything wrong, I'm using the right tools, I do what you do with chamfering, VLD and all. The mandrel smooths out the concentric cutting surface from the chamfer and knocks down the cunt's hair bump/edge at the meeting of the linear grain of the case neck to the concentric grain caused by chamfering. Again, I found doing this made the bullet seating smoother. So, try or don't try. Certainly up to you and I think there has been way, way to much discussion on this for what simple a technique/small nuance step I'm detailing here.

 

[straightshooter1]

good call. I just seated one, the same way I have always done it.

• Alpha SPR (fired 1x) pocket depth 0.1235
• CCI 450 height 0.1200
• After seated, 0.0035 below flush

Looks about right. Although it possible that I sometimes didn't push the primer all the way in when I seated them. I'll measure from now on after seating.

It's not unusual for the type of hand seater you're using to have variations in depth and often that can be mitigated to some extent by holding the squeeze for a longer period of time (kinda hard on old hands like mine). Like John Glidewell mentioned in his post above, I try to get ~.002 of crush and to be get that I have to get at least that, I seat my primer to ~.005 below flush.

Instead of using my Lee hand primer that I got many years ago, I now uses the 21st Century hand primer, which is adjustable to whatever depth I want. Also it has more leverage than the other hand primers making it much easier on these old hands of mine, and has a hard stop for more consistency. It's not cheep, though.

And to quickly and accurately measure seating depths or primer pockets, I use this tool (also, not cheap :

 

[straightshooter1]

I use a bench mounted competition primer seater that adjusts .001 per click. The Frankford arsenal platinum primer seater is a decent entry level adjustable hand seater for the $$. I used one for a couple years. There are many others, it all comes down to how much $$ you want to spend. But you need an adjustable primer seater.

In addition to my 21st Century priming tool I've also got the Frankford Arsenal adjustable priming tool. Though Frankford Arsenal is adjustable, it just doesn't have a good hard stop like the 21st Century tool or like the CPS from Primal Rights and still hard on old hands like mine. Yup, it comes down to if one wants quality equipment and how much one wants to spend.

 

[Malum Prohibitum]

FWIW I use a Hornady Case Prep Duo, but with a VLD chamfer head instead of the standard chamfer tool most come with, the regular chamfer heads are nearly useless with most modern long range projectiles and do more harm than good IMO since they make a sharp ledge.

Forgive my ignorant question, but is that basically like using a VLD chamfer in a cordless drill (my current plan)?

 

[Malum Prohibitum]

- I used the same seating depth that has been producing 1 hole groups (0.050" jump).

- I calculate ES and SD for each of those individual 5-shot groups. then take the average. so each should be in the teens like you said. but they aren't.

I wonder how important small ES and SD are if you are shooting 1 hole groups.

 

[CK1.0]

Forgive my ignorant question, but is that basically like using a VLD chamfer in a cordless drill (my current plan)?

That’s a great way to do it IMHO.

 

[straightshooter1]

I wonder how important small ES and SD are if you are shooting 1 hole groups.

I don't look at ES's and SD's as being very important to group size. For me, they're only important to the extent they tell me how well I'm producing consistent cartridges. Even so, I know that regular ES's at 65 and SD's at 30 are NOT going to give me consistent the "1 hole groups" I'm after. For the most part, I see it as simply telling me about my case prep and the targets tells me everything else.

 

[FredHammer]

In addition to my 21st Century priming tool I've also got the Frankford Arsenal adjustable priming tool. Though Frankford Arsenal is adjustable, it just doesn't have a good hard stop like the 21st Century tool or like the CPS from Primal Rights and still hard on old hands like mine. Yup, it comes down to if one wants quality equipment and how much one wants to spend.

That little light saber looking 21st century priming tool is the fucken mutt’s nuts! Cool & quality ain’t cheap

 

[FredHammer]

Forgive my ignorant question, but is that basically like using a VLD chamfer in a cordless drill (my current plan)?

I’m using the Frankfurt Arsenal 1950s toaster looking brass prep station. So far so good. Prior to that was the Lee bits&bobs.

 

[acudaowner]

teek your load try higher or lower , switch up primers a few of my loads run single digit 5's to double digit 40's or more just by switching primers especially when I use winchester primers thought it all still shoots fine group wise to 600 yards .

 

[markl323]

I wonder how important small ES and SD are if you are shooting 1 hole groups.

sorry I should have been clearer. 1 hole at 100 yards. I wish it was 300

 

[markl323]

It's not unusual for the type of hand seater you're using to have variations in depth and often that can me mitigated to some extent by holding the squeeze for a longer period of time (kinda hard on old hands like mine). Like John Glidewell mentioned in his post above, I try to get ~.002 of crush and to be get that I have to get at least that, I seat my primer to ~.005 below flush.

Instead of using my Lee hand primer that I got many years ago, I now uses the 21st Century hand primer, which is adjustable to whatever depth I want. Also it has more leverage than the other hand primers making it much easier on these old hands of mine, and has a hard stop for more consistency. It's not cheep, though.

View attachment 8222782

And to quickly and accurately measure seating depths or primer pockets, I use this tool (also, not cheap :

View attachment 8222784

Thanks. I had ordered the Frankfort unit per John's recommendation. If it does not work out well I will try this one. The AccuracyOne set will stay in my wish list for now.

Do you think uniforming primer pocket will make a difference? I'm thinking of getting something like this https://www.brownells.com/reloading...-flash-hole/carbide-primer-pocket-uniformers/.

 

[John Glidewell]

Thanks. I had ordered the Frankfort unit per John's recommendation. If it does not work out well I will try this one. The AccuracyOne set will stay in my wish list for now.

Do you think uniforming primer pocket will make a difference? I'm thinking of getting something like this https://www.brownells.com/reloading...-flash-hole/carbide-primer-pocket-uniformers/.

Not for Alpha ocd brass. Quality brass has pretty tight specs.

 

[straightshooter1]

Thanks. I had ordered the Frankfort unit per John's recommendation. If it does not work out well I will try this one. The AccuracyOne set will stay in my wish list for now.

This Frankfort is a good improvement over what you have and as I mentioned in a previous post, I also have it. I was a little disappointed with it in that it didn't have a good hard stop where I could get as consistent seating as I hoped for. . . AND, the leverage isn't really any better than typical hand held primers making hands get tired when doing a lot of priming. The 21st Century one is so much better in every way, though you do have to buy separately the LRP and SRP seating pins.

Do you think uniforming primer pocket will make a difference? I'm thinking of getting something like this https://www.brownells.com/reloading...-flash-hole/carbide-primer-pocket-uniformers/.

For most types of shooting venues, I don't think is makes enough of a difference. If you're a benchrest shooter competing for small aggregates where winning is determined by the .0001", then I'd say a big yes. I do not compete, but I do like to have my cartridges as uniform as possible so that when I see a flyer, I can better investigate and determine what might have caused it. . . often it being the nut holding the rifle. So, I do uniform my pockets and seat the primers uniformly as a way to eliminate any question about issues with that part of the cartridge when I see something I don't like on my targets.

I would not get a pocket uniformer like that as it isn't adjustable. It might work just fine with your Alpha brass if the cutter is set as the right depth. But then, if you use some other brass that tends to have significantly deeper pockets, this uniformer probably won't work.

I have an RCBS pocket uniformer as well as a 21st Century one (see pics below). The latter is much easier to make adjustments and actually contains within cutters for both LRP's and SRP's. Both have carbide cutters, which I feel is important to get good easy cuts in the pockets.

 

[robb_va]

LOL. I was literally dealing with it THIS week, and had been on the phone with alpha to figure it out.

Some of my cases from last week were not feeding at a match. Found out the issue was case mouths were peened to about .273. With a .273 neck reamer like MOST 6mm match chambers, they would not chamber.

Just 15 minutes in the wet tumbler with nothing but water and brass juice was enough to peen the chamfer and roll the edge adding about .003 to the neck diameter. A loaded round is .270. You could feel the lip with a fingernail and the Calipers and Mic confirmed it.

So i just sized, mandrelled, tumbled then trimmed and loaded 600 rounds THIS week, finishing up today. I miced every loaded round and not one was over .271.

So its not bullshit and you have no fucking idea what you are talking about. People need to know to save them these kind of headaches.

I expect you may you have something else going on. Thick case necks with the Alpha brass perhaps. I'd measure the case neck thickness with a ball micrometer.

I have a 6BR .272 NTN chamber. The fired brass (Lapua) comes out at .2710-.2715. I anneal and then resize with a .268 bushing. I don't use an expander ball or mandrel. I tumble in water with pins for an hour. Once the cases are dry, I trim them with a Giraud. My loaded rounds with a Berger 105 VLD are .269. I've never had an issue with them not feeding due to the neck dimension.

 

[robb_va]

LOL. I was literally dealing with it THIS week, and had been on the phone with alpha to figure it out.

Some of my cases from last week were not feeding at a match. Found out the issue was case mouths were peened to about .273. With a .273 neck reamer like MOST 6mm match chambers, they would not chamber.

Just 15 minutes in the wet tumbler with nothing but water and brass juice was enough to peen the chamfer and roll the edge adding about .003 to the neck diameter. A loaded round is .270. You could feel the lip with a fingernail and the Calipers and Mic confirmed it.

So i just sized, mandrelled, tumbled then trimmed and loaded 600 rounds THIS week, finishing up today. I miced every loaded round and not one was over .271.

So its not bullshit and you have no fucking idea what you are talking about. People need to know to save them these kind of headaches.

"You could feel the lip with a fingernail and the Calipers and Mic confirmed it"

Maybe your trimming is leaving a lip on the case.

 

[DeathBeforeDismount]

"You could feel the lip with a fingernail and the Calipers and Mic confirmed it"

Maybe your trimming is leaving a lip on the case.

Nope, I can do a biopsy after I trim. Already explained exactly what it was and why it happened a few times.

 

[robb_va]

Nope, I can do a biopsy after I trim. Already explained exactly what it was and why it happened a few times.

If you say so.

 

[DeathBeforeDismount]

If you say so.

No you just refuse to listen. I am not using a Girald, I am using a henderson. They trim differently, especially the lyman 3 way that the henderson uses, comes out the box. But keep on going on about whatever the hell you are going on about.

 

[robb_va]

No you just refuse to listen. I am not using a Girald, I am using a henderson. They trim differently, especially the lyman 3 way that the henderson uses, comes out the box. But keep on going on about whatever the hell you are going on about.

Just trying to help you out-

I expect you may you have something else going on. Thick case necks with the Alpha brass perhaps. I'd measure the case neck thickness with a ball micrometer.

I have a 6BR .272 NTN chamber. The fired brass (Lapua) comes out at .2710-.2715. I anneal and then resize with a .268 bushing. I don't use an expander ball or mandrel. I tumble in water with pins for an hour. Once the cases are dry, I trim them with a Giraud. My loaded rounds with a Berger 105 VLD are .269. I've never had an issue with them not feeding due to the neck dimension.

 

[Rich4]

Shooting styles can affect velocity too, differing shoulder pressures and time between chambering and firing will also screw with you, possibly more than some reloading practices.

 

[axarob44]

Sometimes when you run the mandrel through the neck too aggressively it puts a slight flare at the mouth of the case. The neck is resisting penetration and flares the end of the neck slightly.

 

[straightshooter1]

Sometimes when you run the mandrel through the neck too aggressively it puts a slight flare at the mouth of the case. The neck is resisting penetration and flares the end of the neck slightly.

That would probably only happen if things were off center, otherwise, speed really isn't an issue. Look at how brass is produced and how fast the production line works.

 

[axarob44]

That would probably only happen if things were off center, otherwise, speed really isn't an issue. Look at how brass is produced and how fast the production line works.

I've had it happen in the past. Pretty symmetrical flare around the circumference. You could be right.

 

[918v]

Did anyone mention donuts? It suddenly dawned on me that donuts may have formed in the necks and are screwing with ES and accuracy.

 

[straightshooter1]

Did anyone mention donuts? It suddenly dawned on me that donuts may have formed in the necks and are screwing with ES and accuracy.

That's a good thought, particularly if he's seating the bullet deep enough where the bearing surface contacts that donut area. There can be enough variance in the bullet's specs where sometimes it touches and sometimes it doesn't when one is just close to it. Though in the OP, he did mention he runs a mandrel through the neck, which will mitigate that issue; even more so if he's annealing his brass properly.