Re: Bartlein T-rifling Barrel
We don't need clock springs on Servo driven CNC rifling machines, Pratt & Whitneys might benefit from them though. Hehe.
We have had very good results with the "transitional" or gain-twist barrels. So far this has been mostly with short range Benchrest shooters, but some long range Bench, Palma, and F-Class shooters have started using them as well.
The twist you would need is based on the bullet you would like to shoot. As far as the amount of "gain", the best results we have seen so far, only a small amount is needed. Depending on barrel length .5 to 1.0 inch of increase is needed. For example, alot of short range Benchrest shooters like a barrel that starts at 14.25 and increases to 13.5 at the muzzle of a 24" barrel.
Taken from an earlier post on barrels
"NBRSA Nationals were last week 13 new National records where set. 3 new world records set.
All with Bartlein Barrels
Examples:
Tony Boyer new Unlimited class record 8 ten shot groups at 100 yards agg. = .189 (previous record was .2195)
Jack Neary LV record of 5 five shot groups at 100 yards = .1482
Tony Boyer won the 3 gun with a grand agg. of .199 this was for the Sporter class, LV class, HV class 100 and 200 yard combined. A total of 150 rounds being fired for these three classes if I have it correct. Yes a grand agg. of .199 for 150 rounds being fired at 100/200 yards.
Top 20 shooters were all using cut rifled barrels.
65% of the top 20 were shooting bartlein
Out of the top 80 shooters (20 from each class Sporter, LV, HV and Unlimited) Bartlein barrels accounted for 60%, Kriegers where 38% and Hart and Shilen had 1% each.
_________________________
George Gardner, G.A. Precision
http://www.gaprecision.net"
Most of those scores were shot with gain twist barrels.
Feel free to give me a call or P.M. if you have any questions.
Thanks,
Brian Birutas
Bartlein Barrels
262-649-1574