Range Report 22 cal 90gr Bergers at 3100fps,twist?

Re: 22 cal 90gr Bergers at 3100fps

Those bullets need every bit of a 1:7" to be fully stabilized, even at 3100 fps. If you're high above sea level, shooting in warm conditions, that will have more of an effect on stability than a couple hundred fps. You might get away with a 1:7.5" at 5000 feet ASL.

Good luck,
-Bryan
 
Re: 22 cal 90gr Bergers at 3100fps

These are results out of a 30" Lilja 1:7 twist.

90SMK
23.5 grains Varget, BR4 primers
M=2675, E=48, S=16

90SMK
23.5 grains RE15, 210M primers
M=2678, E=59, S=9

I didn't bother messing with the 90 Bergers.
 
Re: 22 cal 90gr Bergers at 3100fps

Hi i have fired them in 7 twist barrels and had the 90gr MatchKings stabalise in a 7.8 twist 223.
With the 7 twist i chambered it as a 223 then tested projectiles then ran a 22-250AI chamber reamer in the 80gr matchkings shot awsome i dusted nearly all 90ge projectiles in the 7 twist 22-250AI the Sierra's and bergers all came apart. What calibre do you want to use the problem is the bullets just start to tear apart in 22 cal when pushed to hard when they are that long. If you are going to shoot them hard get an 8 twist or you will blow all of the projectiles up just past the muzzle i have tried it i got the barrel to test the 90's then after i chambered it to 22-250AI i cut the chamber off and now shoot it as a 223 as the extra velocity just kiled them with the 7 twist. i shot it at 300 without flags elevation measures .320 and width of the group is .810 with the first 3 in the same ragged hole that was with 90gr MatchKings.

I think if you want to push them thast hard neck the case to 6mm and shoot a 107 at 3000fps much better barrel life and the projectiles will hold together also it will work.

As for the load i had the 223 deep throated and was using Lapua Match 223 brass realy long throat as it is in a single shot target rifle and 25gr Varget with Rem 7 1/2 primers dont try thst in an AR start at 23 the throat length makes a huge diference the load has been fired in 5 rifles all the same chamber all safe.

 
Re: 22 cal 90gr Bergers at 3100fps

Wild Bill, reeldoc and cheyenne,
Thanks for helping out with Steve's questions. I always do my best to give truthful and complete answers based on my experience and feedback from others, but clearly I don't know it all!

These long bullets are particularly difficult to make universal statements about, they're just so finicky. I spoke with a shooter last week who was disappointed that he could only get 3100-3200 from a 1:7" twist 22-.284 before the bullets blew up. The fact that cheyenne is able to get them to 3500 and their stable from a 1:8" twist is a surprise for me (not that I doubt it).

Bullet failure and 'max attainable velocity' has a lot to do with the condition (roughness) of the bore. The shooter with the .22-284 probably had a rougher barrel. This, in addition to the 1:7" twist probably combined to make the bullets less survivable than cheyenne's rifle, which probably has a smoother barrel (and a 1:8" twist). This line of thought begs the question: how long will cheyennes barrel stay smooth enough to keep from failing them at 3500? I may be wrong, but I suspect that it may not be many 100's of rounds before the barrel becomes rough enough to start failing the bullets.

Regarding thick vs thin jackets; of course the thicks will stand higher velocities than the thins. It's difficult to say precisely how much though; the roughness of the bore will still be an important factor.

Thanks again for sharing your experiences. We're all in this to learn.

Take care,
-Bryan
 
Re: 22 cal 90gr Bergers at 3100fps

Bryan,
My gun has less around 100 rounds down it as of now. I was under the impression that the 90's used a much thicker jacket than the 80's. I never even tried the 80's, I figured they would easily come apart. I was actually pretty surprised that they stabilized out my 8 twist.
Cason
 
Re: 22 cal 90gr Bergers at 3100fps

Hi Brian i was surprised with the Sierra 90's shooting past 600 yards with my hot load in a 223 i could not believe it the temp would have ben around 70 and we are pretty close to sea level. My barrel was lapped to a mirror finish i know as i did it before the lapping it would have been touch and go with any 90gr projectile in 223.

I know the 90gr 22cals and 115gr 6mm's are both on the edge for length of projectiles in regard to bore diameter. I also was certain to make a clear comparison about your bullets compared to Sierra i think some just bag a particular brand and push another with out the facts of the other.

I have found you to be honest with regard to the Bergers and their pluses and minuses without lies and it is a pleasure to see.

If i was to fit another 22 cal barrel for 90gr bullets over 3000fps it would be cut rifled and closer to 8 than 7 just because it seems to help them. As for bullets starting to blow up i am sure at 3500fps the 90's will start to blow up or the barrel will be toast close to 500 rounds. I new a guy shooting 80gr MatchKings in a 22 Cheater he got to 830 rounds when the barrel just died it was toasted.

The thing i have found is that button rifle barrrel makers usualy dont have exact twists as some give the buttons twist and others give a twist a bit slower than they are actualy because of button slipage. I like Cut barrels where twist can be critical because it is dialed in and cut to the exact required twist.

Also i would get abarrel with 5 or 6 lands because the 3 groove barrels can be hard on realy long projectiles in small bores because the lands are wider and distort the projectile more displacing more jacket in the one place.

What calibre are you looking to use to push them at 3100fps.

As for loads i used from H8350, H4931SC, H1000 and up to Retumbo to try diferent engraving pressures and to give the projectile a little slower engraving pressure.

If you were looking at the best barrel for the 90gr projectiles i would try a gain twist barrel finishing at 7.5 twist this should give the lowest pressures on engraving the lands their are a few people playing around with Match Barrels and gain twist.

 
Re: 22 cal 90gr Bergers at 3100fps

Seem like to me.. the limit most conventional construction bullets will tolerate is about ~5200-5300 Revolutions per Second

More than that and that's when you start hearing about bullet blowups.

Probably better to keep a 5000RPS threshold to not get blowups.