Berger Jacket Limitations with Velocity?

[brant89]

I've only heard of slinging jackets off of thinner jacketed bullets, which thinner jacketed bullets usually shoot the most consistent. Those are the bullets that I prefer to shoot Never heard of an accubond, interbond, etc.... slinging a jacket off. As far as the 22 creedmoor, Its hard to deny those who have success with an 8 twist and 80-90gr bullets. Personally, I would still do a 7 twist if I was putting together another 22 creedmoor. I just never think its a safe bet to rely on extra velocity to get to marginal stability.

After my 22BR experience I'm in agreement with you and wish I had gone with a 7 twist and risked the blowups. That being said, the rifle is still showing a lot of promise with the 77's and I might try the 75 ELD when they become available again.

 

[AZShooter]

My experiences vary.

I have a 30" 5R Bartlein 1 in 7.5 twist in 6mm-284 with 105 Berger hybrid target bullets with enough velocity to yield 336,000 RPM. Wore it out at around 1100 rounds and never had any issues with bullet integrity. Cut off 4" inches and rechambered and it is still shooting the 105s with no issues. Slightly slower with 328,800 RPMs.

Had the opposite experience as did a friend. We built 30" 1 in 7 twist 3 groove 7mms. I chose a 7 Rem mag and friend a 7 STW. We used 180 VLD hunting bullets. The STW yielded 318, 857 RPMS the 7 Rem mag 303,428 RPMs.

The STW began to damage the bullets a bit over the 100 round count. The 7 Rem mag closer to 200 rounds. Switched to 180 target with thicker jackets. Another 100 rounds or so and both rifles began to damage the target versions! My friend pulled his barrel and I switched to accubonds and Barnes TTSX.
I believe the damage was done due to the 3 groove throat getting rough and with those large lands it did most of the damage perhaps the RPMs contributed too.

That 7 STW barrel later became a 27.5" long throated 284 win. So far it is handling the 180 hybrid target bullets with no issues. RPMs are 295,714. Time will tell.

 

[KR260]

The land & groove configuration along with the condition of the bore will have a significant impact on whether the jacket gets slung off or not. 5R & 6 groove barrels are less likely to sling jackets off at higher velocities. I've pushed 88 elds to 3350 fps in a 7 twist 6 groove repeatedly with no issues.

I push the 88s to 3100 out of a 7tw 5r 22BR with no issues. Shot some 53gr V-max at 3600 out of the same barrel and they stayed together too.

 

[brant89]

I push the 88s to 3100 out of a 7tw 5r 22BR with no issues. Shot some 53gr V-max at 3600 out of the same barrel and they stayed together too.

Thank you for confirming my poor decision on barrel twist. Lol. I'll be fine with the 77's out to 700 or so which is usually about as far as I shoot and it's supposed to be my trainer/practice rifle anyway. If I need to smash something at long distance I'll grab my 300WM.

 

[Varmint Hunter]

IME - you are less likely to dust bullets in a fast twist barrel if the bullets are coated with a friction reducing product. I used moly in the good old days and it worked great at maintaining the jacket integrity of the 75gr A-Max bullets that I was shooting at 3,670 ft/sec. Even when the throat was well worn the bullets stayed intact.

 

[KR260]

Thank you for confirming my poor decision on barrel twist. Lol. I'll be fine with the 77's out to 700 or so which is usually about as far as I shoot and it's supposed to be my trainer/practice rifle anyway. If I need to smash something at long distance I'll grab my 300WM.

Don't give up on the 22BR. I shot two 3 shot groups at 412 yards that were just over .25" and just under .4" while prepping for a ladder. If I would have checked my target, I would have stopped there. The 88s were very accurate to 1400 yards with little to no recoil. I have some 90gr A-tips, but haven't messed with them.

I did shoot some 75gr ELDM, but there wasn't much veclocity difference over the 88s.

 

[brant89]

Don't give up on the 22BR. I shot two 3 shot groups at 412 yards that were just over .25" and just under .4" while prepping for a ladder. If I would have checked my target, I would have stopped there. The 88s were very accurate to 1400 yards with little to no recoil. I have some 90gr A-tips, but haven't messed with them.

I did shoot some 75gr ELDM, but there wasn't much veclocity difference over the 88s.

I'm definitely not giving up on it. During my first ladder test with the 77's I found a node between 30.4 and 31.0gr of PP 2000-MR that had only 1.125" of vertical and 1.300" horizontal at 400 yards and a velocity of 2940 fps (20" barrel). I'm going to try to get out this weekend to do another ladder within that node at 700 yards. I just know that after 700 the wind is going to push those little guys all over the place.

 

[Elk Hunter 338]

I've seen the 147 come apart in a 7 twist 6.5 saum with 100 rounds on the barrel.

i ran the 105 hybrids up too 3480 in a 6-284 no problems and was hell on coyotes 8 twist

ran the 180 hybrid in the before it was even a pipe dream "28 nosler" @3200 no problems 9 twist

ran the 195 in a 9 twist 7 rum @3200 no problems

ran the 230 @ 3200+ in a 10 twist no problems

run the 80.5 fullbore at 3400+ in an 8 twist 22 creed actually several of these

300 berger at over 3200 in a really big 338 10 twist no problems

 

[gnbruce]

we found the 245 eol s heldup to 360000 rpm out of our 7 twist 30 xc

 

[Elk Hunter 338]

we found the 245 eol s heldup to 360000 rpm out of our 7 twist 30 xc

I know the 7 twist is for the big mono's and you tested to test but in that exact case if you were too build the XC again for the 245 at that speed a 10 twist would be probably the best HUH?

 

[jrock]

Not to the point but I would like to know how the OPs friend achieved that velocity with those bullets. I could only get 3050 to 3100 in a 6.5-300.

 

[gnbruce]

I know the 7 twist is for the big mono's and you tested to test but in that exact case if you were too build the XC again for the 245 at that speed a 10 twist would be probably the best HUH?

we shoot the 30-378 bee with the 240 s in a 10 twist accurate

 

[Mike Matteson]

I have looked into this some, but didn't fully understand. In days gone by there were bullet built that stated on the box not to exceed a muzzle velocity of. Nosler partition use to note on the side of their bullet boxes not to exceed 2900fps. I use a 100gr partition in my 25-06 at that time. The bullet came unscrewed hitting a deer. blood shot the entire side of deer. Never used them again. I do use Nosler Accubonds bullet as my main bullet for hunting. Driving 165gr from 308 Norma Mag @ 3300fps, and no problems from close range out 500yds on deer and elk.
I find the info very interesting, and thanks.

 

[jshepherd61]

So I was out shooting LR with my buddy the other day. He was shooting a 6.5 STW pushing a 156 EOL at 3400fps with great accuracy. It was very intriguing to say the least. 16.5 MOA @ 1000 yards. It got me wondering, how fast can you really push them? And does the thinner jacket of the hunting bullet effect the maximum speed. Has anyone pushed a berger to the jacket failure limit? What were you velocities? And do you need to over twist the bullets to stabilize them at these speeds?

I'm shooting a .28 nos throated for the 195's with 1-8 twist. I push them at 3030fps pretty easy with N570. Now I'm curious about like a 175 @3300 or so. Just my brain churning a little bit. Curious to hear from people who have tinkered with this!!

Yes I have blown up Berger VLD's 142 gr Berger VLD at 3500fps out of my Nosler 26 with a Bartlien 30" barrel actually blew some up at 3,300fps. Was shooting and could not find the hole in the target, so put a full 4x8 sheet of plywood backing up, started seeing multiple holes in the plywood, then started seeing dust fly at 20 yds. We videotaped it with high speed video and at 18 to 20 yards they were grenading! Called Berger they said do not run them past 3,200 fps. Switched to Nosler ABLR an running them at 3,450 fps great accuracy and play hell on Antelope at 1,000 yds.