Twist Questions

[Nvreloader]

What would the BEST twist to use for a 22 LR bbl using the following ammo,
knowing the standard range for twist is around the 1x16" range, give or take a little.

1. Match/Target ammo
2. Standard LR, Plinking/Blasting type,

I have a SWAG that out at the farther ranges 100+ yds, that a tighter twist would be more accurate/better,
since the bullet is in SUBSONIC mode, and it would better all around to have the pointie end going first.

I want to try some of those 60+gr ammo at the LONG Ranges 100yds to 500yds,
and I think it would require/need around a 1x9 " twist or slightly faster twist to keep everything in within the ball park.

What I don't know is if, the faster twists would hurt the accuracy,
of the standard 22 LR bullets being used for Plinking/Hunting and Target/Match ammo etc.

Anyone have some reliable info, thoughts or suggestions??
Maybe a site with answers/information.

This itch NEEDS scratching real bad!!!!!!

Tia,
Don

 

[stgw77]

I would choose 1:16" standard twist or max 16.5" twist...you can not go wrong with it. Some rimfire benchrest shooters successfuly use 17" twist, while others using this twist report good groups in summer and bad groups in winter (lower velocity, bullets not fully stabilized). You shoud take in mind, that most best rimfire barrels are button rifled (Rock creek/Mullerworks, Lilja, Benchmark, Broughton) and using this metod twist is not necessary dead on like single point cut rifled barrels. Take 16" twist and be safe.

 

[stgw77]

BTW, almost all match rimfire ammo (Eley Tenex, Lapua Midas+, RWS R50) is allready subsonic when the bullet leaves the muzzle...1030-1080 FPS is standard target velocity nowdays, and they work very well also on 100 yards and more...

 

['Freak]

I see it being said that the 60 grain stuff is long enough that it should require something between 1 in 9 to 1 in 11.25 to stabilize, depending who wrote it. Even from a 1 in 9 nobody is singing praises of any sort of half decent accuracy no matter what the distance. Try all the best of the 40 grain stuff running it through a 1 in 16 barrel. You might wanna consult a good ballistics calculator before making plans on much beyond 300.

 

[Outrider27]

What OleFreak said. If you want to shoot the 60gr Aquila SSS round a lot, you are going to need a dedicated rifle with a 1 in 9 twist barrel to get reliable, consistent accuracy. Our experience has been that the accuracy of HV, Std. velocity and Subsonic rounds in the 36 to 40gr range in a 1 in 9 twist is mediocre, thought the testing we have done was primarily aimed at seeing what the 60gr round did in 1 in 16 and 1 in 15 twist rifles, not the other way around. If you want to shoot "normal" weight projectiles, use a normal 1 in 16 twist and have fun.

If you want some info on performance of the 60gr round, see post #6 in the thread below; it is a condensed version of a test I did for a Class II/III dealer for his customers into suppressed .22 rimfire rifles.

http://www.rimfirecentral.com/forums/showthread.php?t=553065&highlight=Outrider

If you practice at 150 to 200 yards with 40gr ammo, you will find that your trajectories and wind corrections are essentially the same as a 308 Win. rifle at 800 to 1000 yards. Nice side benefit.

 

[dickn52]

I'm running gain twist barrels from Bartlein. ".22rf Barrel .217 x .222, 4 groove, "T" style rifling 16.5 to 15.98 twist, S.S. 1.050" str. x 24" finish length." Drives tacks all day long.