PVA 212 Seneca

[Dogtown]

For the 212 in a .300 Norma Mag, I seem to have a solid load at 88.5gr N565 with a long 3.842” COAL, giving me 3165fps out of a 28” 1:8 barrel. I just came from the range to confirm the load at 100 & 300 yards and it’s a consistent 0.5MOA. Next weekend I’ll be testing them at much further distances.

My barrel has a long throat as it was cut for long 230-250gr class jacketed bullets, but it turns out the Seneca bullet profile is such that a long throat isn’t needed even though the bullets are close to 2” long. At 3.842” COAL I’m still seating the bullets out a bit, close to mag length in SRS, and jumping close to 0.1”, but groups are nice.

Something thats becoming a bit more clear to me is that this load is really approaching pressure signs. No ejector marks or cratered primers, but this time around it seems I’m getting the slightest tiny bit of flattening. Enough so that if they don’t perform well at distance, then I may start over using N570 now that I have a pair of big jugs of it. N565 definitely gets them approaching 3200fps, but I’m confident N570 could get them to 3100fps well clear of any pressure. And then when N568 is released, that might be best optimized powder.

Overall this bullet isn’t really all that picky it seems. My last trip to the range was shooting seating depth increments and all were pretty consistent at 0.5MOA +/- 0.1, which isn’t something I’ve seen outside of my 6.5x47L loads. Usually the periodic expansion and contraction of groups tends to be more amplified, from my experience.

If these perform well I plan to order a longer 32-36” barrel with a faster 1:6.5 twist to see what it can do with the 241s. Running the numbers, that bullet at 3000fps would rival a lot of .375CT loads.

 

[NamibHunter]

For the 212 in a .300 Norma Mag, I seem to have a solid load at 88.5gr N565 with a long 3.842” COAL, giving me 3165fps out of a 28” 1:8 barrel. I just came from the range to confirm the load at 100 & 300 yards and it’s a consistent 0.5MOA. Next weekend I’ll be testing them at much further distances.

My barrel has a long throat as it was cut for long 230-250gr class jacketed bullets, but it turns out the Seneca bullet profile is such that a long throat isn’t needed even though the bullets are close to 2” long. At 3.842” COAL I’m still seating the bullets out a bit, close to mag length in SRS, and jumping close to 0.1”, but groups are nice.

Something thats becoming a bit more clear to me is that this load is really approaching pressure signs. No ejector marks or cratered primers, but this time around it seems I’m getting the slightest tiny bit of flattening. Enough so that if they don’t perform well at distance, then I may start over using N570 now that I have a pair of big jugs of it. N565 definitely gets them approaching 3200fps, but I’m confident N570 could get them to 3100fps well clear of any pressure. And then when N568 is released, that might be best optimized powder.

Overall this bullet isn’t really all that picky it seems. My last trip to the range was shooting seating depth increments and all were pretty consistent at 0.5MOA +/- 0.1, which isn’t something I’ve seen outside of my 6.5x47L loads. Usually the periodic expansion and contraction of groups tends to be more amplified, from my experience.

If these perform well I plan to order a longer 32-36” barrel with a faster 1:6.5 twist to see what it can do with the 241s. Running the numbers, that bullet at 3000fps would rival a lot of .375CT loads.

Very impressive result sir!

I see PVA recommends a 0.165” freebore for the 241 Seneca on their web site. That is surprisingly short for such a long copper bullet, but i can see the reason for that: It has a very very pointed shape! It seems that almost 1.6” of the nose is sitting inside the barrel, before the ogive touches the lands.

Curious to know why you are considering a 6.5 twist barrel. What is the ideal SG if you need for a long mono to transition into subsonic region? I noticed that PVA recommends a 7 twist. Then again CEB on their web site recommends you go a full 1.0 faster on twist rate than “needed”, if you want the projectile to work reliably into the subsonic zone. So you may have a point there!

 

[brianf]

Very impressive result sir!

I see PVA recommends a 0.165” freebore for the 241 Seneca on their web site. That is surprisingly short for such a long copper bullet, but i can see the reason for that: It has a very very pointed shape! It seems that almost 1.6” of the nose is sitting inside the barrel, before the ogive touches the lands.

Curious to know why you are considering a 6.5 twist barrel. What is the ideal SG if you need for a long mono to transition into subsonic region? I noticed that PVA recommends a 7 twist. Then again CEB on their web site recommends you go a full 1.0 faster on twist rate than “needed”, if you want the projectile to work reliably into the subsonic zone. So you may have a point there!

i think this is where we might go wrong...but im just bs-ing

i believe that solids should be shot at supersonic distances only almost as a per caliber range extender

with the higher bc's and such one should prob go up in weight or caliber rather then flirt with transition.

work on pushing them faster rather to wring out the last of that BC rather than deal with the last 100 yards that might become erratic as the environmentals change during the day

just me though

 

[Dogtown]

Curious to know why you are considering a 6.5 twist barrel. What is the ideal SG if you need for a long mono to transition into subsonic region? I noticed that PVA recommends a 7 twist. Then again CEB on their web site recommends you go a full 1.0 faster on twist rate than “needed”, if you want the projectile to work reliably into the subsonic zone. So you may have a point there!

Well obviously a faster twist is needed for a longer bullet, but my thinking for going faster than the required 1:7 twist is just based on stuff I've been hearing from folks who shoot further and more often than me.

 

[gnochi]

Well obviously a faster twist is needed for a longer bullet, but my thinking for going faster than the required 1:7 twist is just based on stuff I've been hearing from folks who shoot further and more often than me.

You trade dispersion for BC and transonic behavior; it’s not strictly an improvement.

 

[Dogtown]

Interesting.

I was under the impression that the solids handle faster twists better due to the nature of being monolithic, and that guys were pushing past normal SG values and getting more stability through transonic? Are you saying that abnormally high SG values result in groups opening up? I'm happy to be corrected.

 

[gnochi]

Interesting.

I was under the impression that the solids handle faster twists better due to the nature of being monolithic, and that guys were pushing past normal SG values and getting more stability through transonic? Are you saying that abnormally high SG values result in groups opening up? I'm happy to be corrected.

All of that is true, as it turns out:

• Lead is not strong enough to support a bullet spinning faster than ~300k rpm (larger-diameter bullets would have a slower spin speed limit). Copper jackets aren’t strong enough to keep the lead intact much past that. Solid copper, however, does fine.
• Faster twist means more stable, better transonic transitions, and a measurably higher BC.
• Faster twist also means that the bullet path is much more sensitive to microscopic defects and misalignment, so group size will be larger. This is why benchrest shooters go for marginal stability and fast shooting once they figure out the wind.
• Not sure we understand ballistics/etc well enough to determine whether a faster twist that’s gone subsonic has a larger or smaller group size than the slower twist, but my gut is that the faster twist is an improvement… to a point.

 

[Dogtown]

This is why benchrest shooters go for marginal stability and fast shooting once they figure out the wind.

I was unaware that's why they were shooting that way - very interesting.

So I guess 1:7 for the 241s is ideal.

 

[NamibHunter]

All of that is true, as it turns out:

• Lead is not strong enough to support a bullet spinning faster than ~300k rpm (larger-diameter bullets would have a slower spin speed limit). Copper jackets aren’t strong enough to keep the lead intact much past that. Solid copper, however, does fine.
• Faster twist means more stable, better transonic transitions, and a measurably higher BC.
• Faster twist also means that the bullet path is much more sensitive to microscopic defects and misalignment, so group size will be larger. This is why benchrest shooters go for marginal stability and fast shooting once they figure out the wind.
• Not sure we understand ballistics/etc well enough to determine whether a faster twist that’s gone subsonic has a larger or smaller group size than the slower twist, but my gut is that the faster twist is an improvement… to a point.

Good summary. I was looking at a 6.5 twist 30 cal barrel some time ago, trying to get the SG for the 241 Seneca above 2, but gave up on that idea, and ordered a 7 twist barrel. At least it will still be able to shoot heavy lead core bullets at just below 300,000 rpm, if the monos don’t work out. Might have to limit speed to prevent disintegration, but doable.

I wish somebody would construct a detailed WEZ simulation using a 4DOF model, where concentricity defects can be accurately simulated. Then you could potentially investigate the trade-offs, and figure out the ideal twist rate. If you could actually measure the concentricity SD…. Might not be that simple.

What i have noticed from the data published by Litz about the Clark’s Knob ELR event: Almost all of the top 15 competitors had SG between 1.9 and 3.0. Most were around 2.3, which for the Seneca 241 at 2,800 fps converts to 6.0 twist….

But the trade-off is that a 6.5 or a 6 twist barrel will likely not work with lead core bullets (disintegration is a real possibility). Then dedicated barrels are the only way forward.

High twist rate barrels will amplify any small bullet inconsistencies, and that may well open up the 1000 yard groups, and beyond. Trade-offs.

 

[Dogtown]

Even though I've got a pretty good .300NM load using the 212s with N565, it's a bit on the hot side so this past weekend I went back to N570 to see if I could come up with something similar but not so hot. In the process I also did some neck tension testing, which kind of sucks when the bullets are this expensive but it confirmed my suspicions. It seems like these bullets, at least in my barrel, really prefer pretty tight necks.

My previous jacketed bullet loads seemed to like a neck ID of 0.3065" (using 21st Century mandrels), but with the 212 Seneca I was getting all-holes-touching sized groups with tighter 0.304" and 0.3045" IDs. Yes, this may not be all that statistically significant because I was only shooting 3-shot groups with each neck size (same parameters otherwise), but it's enough for me to just switch to those tighter necks from here on out with this bullet. I was also able to seat them a bit longer at 3.910" while still not touching the lands, but remaining magazine loadable.

 

[NamibHunter]

Even though I've got a pretty good .300NM load using the 212s with N565, it's a bit on the hot side so this past weekend I went back to N570 to see if I could come up with something similar but not so hot. In the process I also did some neck tension testing, which kind of sucks when the bullets are this expensive but it confirmed my suspicions. It seems like these bullets, at least in my barrel, really prefer pretty tight necks.

My previous jacketed bullet loads seemed to like a neck ID of 0.3065" (using 21st Century mandrels), but with the 212 Seneca I was getting all-holes-touching sized groups with tighter 0.304" and 0.3045" IDs. Yes, this may not be all that statistically significant because I was only shooting 3-shot groups with each neck size (same parameters otherwise), but it's enough for me to just switch to those tighter necks from here on out with this bullet. I was also able to seat them a bit longer at 3.910" while still not touching the lands, but remaining magazine loadable.

Interesting result.

Did i understand you correctly in that you made changes to both seating depth (longer COAL, same for both batches) AND you also changed neck tension/interference fit from 1.5 thou to 2.5 thou (so different for the two batches)?

If that is correct, then the improvements in group size might be from the combo of the two effects, and not just the increase in neck tension. [If i misunderstood, then please just ignore.]

Curious what annealing method you use, and how often you anneal? Reason i ask: I use an AMP machine in aztec mode, and that makes the brass pretty soft. Definitely softer than my prior flame annealing method. I have a set of modified pin gauges in 0.5 thou increments, modified (tapered on one end) to work in the Porter Precision mandrel die (highly recommended). What i find is that if i try to use anything more than a 0.5 thou interference fit, that the bullet resizes the neck. I do get different sizing force (measured with the K&M force pack), but it seems that is mostly due to higher resizing force needed if the interference fit goes beyond 0.5 thou. [Maybe the magic nr is 0.4 thou, hard to know.]

If i carefully pull the bullet out with a Forster bullet pulling die, and then seat a fresh bullet (once again applying Imperial dry lube), that the seating force is way lower. The second round seating force should be very close to the actual force needed in tje chamber to push the bullet out of the neck, as no resising (plastic deformation) is occurring on seating a bullet the second time round).

Not discounting interference fit as a tuning variable: I have seen that speed and group sizes can be quite different between 1.5 thou and 2.5 thou neck sizing. I am guessing that the additional stretching of the neck causes more work hardening, and that changes the actual grip force on the bullet. So an indirect mechanism is at work here.

My main points are:

1) Bullets can easily resize undersize soft annealed necks, and that the observed force depends on accumulated work hardening (nr of firings), degree or annealing achieved in the latest anneal, and initial brass composition/metallurgy (brand of brass). [You hear of people who do not anneal who say they get best accuracy after 2 or 3 firings…. I guess they have to wait for sufficient springback to show up?]

2) The force needed to pull (or push) a bullet OUT of the neck
is what really matters, not the seating force needed to push it INTO the neck PLUS resize the soft neck on the way in. [Of course, we have no instruments today to measure pull force.]

3) My assertion is that the force measured during the second bullet seating attempt is more indicative of the actual force (and the required gas pressure) needed to dislodge the bullet and drive it out of the neck and into the lands. [I realize it is very impractical to load this way, and i am not proposing it. But it is an interesting experiment to do at least once.]

You probably could achieve similar increased grip force (and results on target) compared to a mandrel that leaves 2.5 thou of interference fit by changing (reducing) the AMP code. Or reducing your flame annealing time by half a second.

Apparently there is a new AMP software feature that can do that, a way to plus or minus some increments to the aztec code without overcooking the neck. My AMP does not show the option, presumably i will first have to upgrade my software.

Has anybody tried it?

 

[Dogtown]

Interesting result.

Did i understand you correctly in that you made changes to both seating depth (longer COAL, same for both batches) AND you also changed neck tension/interference fit from 1.5 thou to 2.5 thou (so different for the two batches)?

No, I did a control group with the previous 3.842" COAL and previous neck tension before testing longer COAL and tighter neck tension. It's weird, but I don't think these bullets are all that sensitive to COAL changes, but they definitely prefer tighter necks in my barrel.

Curious what annealing method you use, and how often you anneal?

AMP as well, after every firing. I also neck turn for uniformity.

 

[NamibHunter]

No, I did a control group with the previous 3.842" COAL and previous neck tension before testing longer COAL and tighter neck tension. It's weird, but I don't think these bullets are all that sensitive to COAL changes, but they definitely prefer tighter necks in my barrel.


AMP as well, after every firing. I also neck turn for uniformity.

Thanks for the details, that is helpful.

Glad to hear the bullet is not overly jump sensitive, that will make it easier to tune the load.

 

[Dogtown]

Yeah it’s really unlike any bullet I’ve used before. The first time I shot a string of groups with incremental charge weights, I didn’t get the sinusoidal grow-shrink across the target. They were all really tight and my ES levels were all crazy low.

 

[Dogtown]

So yep, going back and revisiting N570 was a good idea. Velocities weren’t as high as N565 but I’m close and still a couple grains below pressure signs. I tested 87-90gr on this round and once again all shots grouped under 1 MOA, with 89gr being the size and ES winner. Again, these seem to like relative tight necks, so I sized them with a 0.3045” mandrel. COAL was 3.910”

Because these bullets are so pricey I’ll just load up a batch and test them at distance instead of further refining them.

 

[Schw15]

Are These bullets showing consistent bc bullet to bullet? Asking not stating

 

[NamibHunter]

Good to know bullet BC consistency is good. What waterline (verical dispersion) do you get at ELR distances?

One can roughly back-calculate BC variation by assuming that half the vertical dispersion is die to BC variation, and the rest is shooter error, variable updraughts caused by topology, wind blowing straight from the front or back with major wind speed variation, etc.

 

[Schw15]

You guys running a 1-8 twist or or 1-7 for these bullets?

 

[NamibHunter]

Have a 1:7 twist on order to run the 241 Seneca. Dealing with long wait time.

Many people tell me i will see bullets blow up if i try to shoot lighter lead core bullets at this twist rate. We shall see. Might have to pick the “wrong” powder and keep speed around 2750 fps when shooting 210’s and 220’s…. Less than ideal, but probably workable.

Will order a second barrel with a 1:9 twist if that proves to be a problem. It is an MPA switch barrel setup. Might take both barrels to the range and swap them when one gets too hot!

 

[Schw15]

Have a 1:7 twist on order to run the 241 Seneca. Long wait times.

Many people tell me i will see bullets blow up if i try to shoot lighter lead core bullets at this twist rate. We shall see. Might have to pick the “wrong” powder and keep speed around 2750 fps when shooting 210’s and 220’s…

Yeah I wouldn't try to push them they will blow at that twist. Basically committed to solids

 

[Dogtown]

You guys running a 1-8 twist or or 1-7 for these bullets?

I'm using 1:8 with the 212s; have a 1:7 on order for 241s.

 

[Schw15]

I'm using 1:8 with the 212s; have a 1:7 on order for 241s.

I was running numbers with 212 1-8 twist I wasn't to stable in my app. I live at 5400 feet too

 

[NamibHunter]

I'm using 1:8 with the 212s; have a 1:7 on order for 241s.

Let us know how the 241’s perform when you get your barrel. REALLY interested in what that bullet can do!

Just possibly it could give 375 ballistic performance in a 300 plarform, with half the recoil. But bullet splash will also be behalf the puff of dust…

 

[NamibHunter]

I was running numbers with 212 1-8 twist I wasn't to stable in my app. I live at 5400 feet too

Not sure how accurate Strelok Pro is for stability factor calcs, but i get SF=1.49 with an 8 twist barrel for the 212 Seneca at almost sea level. That is lowish for a mono, but it should be sufficient for the supersonic range? Are you concerned that it might not safely transition to subsonic in an ELR application?

Half the wind drift of a 6.5 Creedmoor firing 140 Hybrids. Amazing performance.

 

[Schw15]

Not sure how accurate Strelok Pro is for stability factor calcs, but i get SF=1.49 with an 8 twist barrel for the 212 Seneca at almost sea level. That is lowish for a mono, but it should be sufficient for the supersonic range? Are you concerned that it might not safely transition to subsonic in an ELR application?

View attachment 7689310

Half the wind drift of a 6.5 Creedmoor firing 140 Hybrids. Amazing performance.

Need at least 1.50 to be stable full bc

 

[NamibHunter]

Need at least 1.50 to be stable full bc

Yep, fair point. You then need 2950 fps or a little more for the SF to exceed 1.50. Doable in a large magnum.

What caliber are you intending to use, and what is your planned barrel length?

It seems to me that most folks converge on the same conclusion: One dedicated barrel with a 7 twist for the super long monos, and another 8.5 or 9 twist barrel for the heavy lead core options. ELR soon gets to be an expensive new hobby!

Btw, I am trying to contain costs by limiting myself to a short action switch barrel rifle i already have. But design compromises lurk around every corner…

 

[Schw15]

Yep, fair point. You then need 2950 fps or a little more for the SF to exceed 1.50. Doable in a large magnum.

What caliber are you intending to use, and what is your planned barrel length?

Just running numbers to see. It would be 300 win mag. Haven't decided for on everything but I think a 1-7 twist is best for 212

 

[NamibHunter]

Just running numbers to see. It would be 300 win mag. Haven't decided for on everything but I think a 1-7 twist is best for 212

Speaking of compromises: That 7 twist barrel will squeeze all the available BC out of that superb rocket shaped mono bullet, and significantly ease the transition into subsonic flight, very likely making hits possible beyond 2,500 yards if you use the Nightforce Prism.

But small errors in concentricity will get amplified (like bullet surface smoothness and other density inperfections, or one rifled groove perhaps being 0.2 thou deeper than the others), and that will open up the groups - even at 500 yards if a very fast twist is used.

Well-made monos can be very concentric - if the lathe has top quality bearings that have not yet worn out. And if the copper barstock is top notch, and has no voids and no inclusions.

Somewhere among all these design trade offs, there is a perfect balancing point for each range of projectiles you may wish to use. Not sure if that is 7.0 or 7.6.

 

[Schw15]

I'm using 1:8 with the 212s; have a 1:7 on order for 241s.

What barrel you have on order?

 

[Schw15]

Speaking of compromises: That 7 twist barrel will squeeze all the available BC out of that superb rocket shaped mono bullet, and significantly ease the transition into subsonic flight, very likely making hits possible beyond 2,500 yards if you use the Nightforce Prism.

But small errors in concentricity will get amplified (like bullet surface smoothness and other density inperfections, or one rifled groove perhaps being 0.2 thou deeper than the others), and that will open up the groups - even at 500 yards if a very fast twist is used.

Well made monos are very concentric - if the lathe has top quality bearings that have not yet worn out.

Somewhere among all these design trade offs, there is a perfect balancing point. Not sure if that is 7.0 or 7.6.

Yeah but the 7 you can shoot 212 or 241 fine. And then any other solid you would like.

 

[Dogtown]

What barrel you have on order?

32” 1:7 Bartlein 5R

 

[Schw15]

32” 1:7 Bartlein 5R

How long the wait time on that badboy

 

[Schw15]

I got mixed up and 1-8 should work good with the 212. Borderline but 7.5 be best I think. It's funny the 198 seems to say 1-9 but I think it needs a little more help also. But the performance wow be very exciting to see at 1 mile plus

 

[Dogtown]

How long the wait time on that badboy

6-9 months

 

[Dogtown]

212s are working fine in a 1:8 .300NM and I’ve pushed them from 3075-3250fps.

 

[Schw15]

6-9 months

Not crazy really. You get the new barrel material?

 

[Schw15]

212s are working fine in a 1:8 .300NM and I’ve pushed them from 3075-3250fps.

Mine would be a 300 win mag prolly 2900 to 2950 if I did it.

 

[NamibHunter]

32” 1:7 Bartlein 5R

That long 32” barrel should get the speed up another 150 - 200 fps over book speed if you experiment with slower powders. Curious what action you are using?

I have been told that some actions (like mine, Curtis Axiom, and most factory rifles) are not beefy enough to host a heavy profile barrel longer than 28” without distorting the contact between the bolt lugs and action. Apparently, during firing the bottom lug may pull away from its mating surface. Is the theory correct that some rifles will get inaccurate if the barrel is too long or too heavy? How long is too long?

I believe there may be something to this: I have a 30” Shilen Select Match barrel on my Savage 12 (large shank) rifle in a V-block HS Precision fiberglass stock, and it does 0.6-0.7” groups, while the original 26” factory barrel did 0.25-0.3” groups when new. I am thinking about cutting it back to 27” and perhaps re-barreling to 6.5 PRC.

I know that some 338 and most all 375/416/50 cal actions are much bigger, heavier and stronger, and some can handle barrels up to 36”.

Any sage advice on max barrel length?

 

[Dogtown]

It‘s a first gen SRS.
I have a few heavy contour long barrels that I use with it. My current .300NM is a 28” with 1.045” straight contour. I also have two 36” .338LM Improved 40 barrels, one that’s also straight 1.045” and the one in this picture that’s step contoured from 1.250” down to 0.9” ish. The barrel tenon on the SRS is about 5” making it a pretty solid platform.

The only reason I ordered the 32” over getting another 28” is because experimenting in Quickload told me it was going to get the 241s up to 3000fps with ease.

 

[Dogtown]

For comparison from left:

- 36” 1.045” straight contour .338
- 36” step contour .338
- 26” medium Palma contour 6.5mm

 

[Schw15]

That long 32” barrel should get the speed up another 150 - 200 fps over book speed if you experiment with slower powders. Curious what action you are using?

I have been told that some actions (like mine, Curtis Axiom, and most factory rifles) are not beefy enough to host a heavy profile barrel longer than 28” without distorting the contact between the bolt lugs and action. Apparently, during firing the bottom lug may pull away from its mating surface. Is the theory correct that some rifles will get inaccurate if the barrel is too long or too heavy? How long is too long?

I believe there may be something to this: I have a 30” Shilen Select Match barrel on my Savage 12 (large shank) rifle in a V-block HS Precision fiberglass stock, and it does 0.6-0.7” groups, while the original 26” factory barrel did 0.25-0.3” groups when new. I am thinking about cutting it back to 27” and perhaps re-barreling to 6.5 PRC.

I know that some 338 and most all 375/416/50 cal actions are much bigger, heavier and stronger, and some can handle barrels up to 36”.

Any sage advice on max barrel length?

Technically never really heard that. I run a arc Nuclues and have 30 inch to 26 inch barrels. 1 inch at muzzle and I have never seen any issues. My one barrel is a 7mm-300 win mag 29 inch 1 inch at muzzle plus a brake 4 inches hanging off the end. It is a barrel nut barrel I redloctite the nut then torque it like shoulder barrel at 40 ft. No issues at all shoot it to 1 Mile with ease.

 

[gnochi]

Technically never really heard that. I run a arc Nuclues and have 30 inch to 26 inch barrels. 1 inch at muzzle and I have never seen any issues. My one barrel is a 7mm-300 win mag 29 inch 1 inch at muzzle plus a brake 4 inches hanging off the end. It is a barrel nut barrel I redloctite the nut then torque it like shoulder barrel at 40 ft. No issues at all shoot it to 1 Mile with ease.

The nucleus also auto-centers if the lugs do shift slightly, so it’ll never be a problem on that action until it’s super unsafe to shoot. Also at that point you mount the barrel and let the action float.

TBH I’m not certain that it’s a problem with anything but maybe a base R700, and that’s because there might be no lug contact to begin with.

 

[NamibHunter]

Technically never really heard that. I run a arc Nuclues and have 30 inch to 26 inch barrels. 1 inch at muzzle and I have never seen any issues. My one barrel is a 7mm-300 win mag 29 inch 1 inch at muzzle plus a brake 4 inches hanging off the end. It is a barrel nut barrel I redloctite the nut then torque it like shoulder barrel at 40 ft. No issues at all shoot it to 1 Mile with ease.

Thanks for the info, this is most helpful!

I believe the SRS has a very robust action (refused to blow up even with doing rather suicidal things - according that famous utube video!), so probably way more stiff than a Savage factory action.

I’m still tempted to cut my 30” barrel back to 27” or so, and see if that improves accuracy. [Of course, any improvement might come from fixing a bas crown, or the bore diameter opening up 0.5 thou towards the end of the barrel…]

Or should j take the chance to have the barrel reprofiled to 0.8” at the muzzle? I realize that may ruin the barrel if any residual stress is present. Do a cryogenic stress relief treatment before reprofiling it?

 

[Schw15]

View attachment 7689716
It‘s a first gen SRS.
I have a few heavy contour long barrels that I use with it. My current .300NM is a 28” with 1.045” straight contour. I also have two 36” .338LM Improved 40 barrels, one that’s also straight 1.045” and the one in this picture that’s step contoured from 1.250” down to 0.9” ish. The barrel tenon on the SRS is about 5” making it a pretty solid platform.

The only reason I ordered the 32” over getting another 28” is because experimenting in Quickload told me it was going to get the 241s up to 3000fps with ease.

Have you reloaded another solid bullets or just the 212 from pva? Just curious if you find them all easy? I have reloaded for a few the 151 pva hunting bullet was super easy and great bullet.

 

[gnochi]

Thanks for the info, this is most helpful!

I believe the SRS has a very robust action (refused to blow up even with doing rather suicidal things - according that famous utube video!), so probably way more stiff than a Savage factory action.

I’m still tempted to cut my 30” barrel back to 27” or so, and see if that improves accuracy. [Of course, any improvement might come from fixing a bas crown, or the bore diameter opening up 0.5 thou towards the end of the barrel…]

Or should j take the chance to have the barrel reprofiled to 0.8” at the muzzle? I realize that may ruin the barrel if any residual stress is present. Do a cryogenic stress relief treatment before reprofiling it?

I wouldn’t bother. Just see how it shoots.

 

[Dogtown]

Have you reloaded another solid bullets or just the 212 from pva? Just curious if you find them all easy? I have reloaded for a few the 151 pva hunting bullet was super easy and great bullet.

I have shot many different solids over the past 15+ years, but the 212gr Seneca is so far the only one from PVA I've shot.

 

[Schw15]

I have shot many different solids over the past 15+ years, but the 212gr Seneca is so far the only one from PVA I've shot.

Do you feel there one of the best?

 

[Dogtown]

Don't know - I won't be able to test them at ELR distances until October. I just know that once I figured out they preferred tight necks in my barrel and weren't fussy about seating depth, load dev got really interesting with groups remaining tight across a wide range of charge weights. I've honestly never seen that before and instead expected the typical open-up/shrink periodic grouping pattern.

I started out with the LRBT solids around 2006 and while they performed far and away better than any jacketed magnum bullet, they fouled the bore annoyingly quick. There were some other solids I shot from some groups in development, but none were much of an improvement. I also shot quite a bit of the Lehigh solids in .338 cal as well as solids from Cutting Edge. None really worked well enough for me to use long term in .338LM and .338LM Improved 40, both of which I had excellent 250 & 300gr jacketed bullets for. I started testing the Flatline 285gr solids a few years ago and those looked promising, but I had to bench those until recently and now I'm back to doing load dev with them.

I started shooting .300NM a year ago and really struggled to develop loads with jacketed bullets that performed well at distance. Then most recently here I discovered the Seneca bullets and gave the 212s a try. Results were so impressive that I think I'm just going to shoot those in this barrel from here on out.

 

[Schw15]

Don't know - I won't be able to test them at ELR distances until October. I just know that once I figured out they preferred tight necks in my barrel and weren't fussy about seating depth, load dev got really interesting with groups remaining tight across a wide range of charge weights. I've honestly never seen that before and instead expected the typical open-up/shrink periodic grouping pattern.

I started out with the LRBT solids around 2006 and while they performed far and away better than any jacketed magnum bullet, they fouled the bore annoyingly quick. There were some other solids I shot from some groups in development, but none were much of an improvement. I also shot quite a bit of the Lehigh solids in .338 cal as well as solids from Cutting Edge. None really worked well enough for me to use long term in .338LM and .338LM Improved 40, both of which I had excellent 250 & 300gr jacketed bullets for. I started testing the Flatline 285gr solids a few years ago and those looked promising, but I had to bench those until recently and now I'm back to doing load dev with them.

I started shooting .300NM a year ago and really struggled to develop loads with jacketed bullets that performed well at distance. Then most recently here I discovered the Seneca bullets and gave the 212s a try. Results were so impressive that I think I'm just going to shoot those in this barrel from here on out.

Do you shoot elr competitions? The only downfall seems to be spotting with solids at distances. 1760 plus

 

[Dogtown]

Yes, I have in the past and plan to again, but a majority of my ELR shooting at distance isn't during competitions. Yes, spotting impacts from solids can be tricky, but there are ways to make it easier. Depending on the number of folks I'm shooting with on a given day, we'll often setup someone to be a downrange spotter when distances stretch past 2000 yards.