The sinner rifle has a barrel with a 1-14 twist. I believe its made by lothar walther
Anybody know of an air rifle barrel with a twist of less than 1 in 16.I read once that less twist is more accurate at long range above 50 yds.Cheers chaps
The sinner rifle has a barrel with a 1-14 twist. I believe its made by lothar walther
Air arms ev2 mk4 and new FTP900 = 1 in 14
The 22LR Lothar Walther barrels used in the Drummen Sinner all have a twist of 416 mm which equals to a twist of 1-16,38
Anybody found any notable difference in accuracy at long range with 1-14 as oppose to 1-16,i'm thinking even slower twist rate.I should have been clearer by saying spin speed e.g. 1-20 is less than(slower) 1-16.That is one revolution in 20 as oppose to one in 16.Hope this is understandable,non FAC also only normal air rifle pellets.
Last edited by landymick; 12-10-2013 at 08:52 PM. Reason: extra info
Projectile weight, size, speed, and also barrel length and altitude all have a bearing on the optimum twist rate for barrels.
for an 8.4grain, .177 @ 784fps the closest optimum twist rate is 1 in 14 with a 17 inch barrel, and that'll be good from sea level upto 10.000 foot.
for the closest you are looking for, please see my previous post
TX200 1:17",
HW97 1:15.5" ,
Rapid Mk 1 1:14",
Steyr 110ft 1:17" ,
HW100 1:16",
CZ (S200) 1:18.5",
BSA 1:18.5",
Steyr barley twist 1:15.5"
HW50 1:16"
(these are all measured from my own rifles/barrels apart from the Steyr barley twist, you may find that your barrel is different, it seems manufacturers change the barrels/twist rate from time to time)
Officially the LW barrels (which are fitted to a lot of different rifles) are 1:450mm (1:17.71"), this includes the polygonal barrels.
I have been told that slow twist rates (1:20+) would be best for accuracy but I have also been told that a faster twist rate is better in the wind. This is for sub 12ftlbs.
Last edited by XTX; 25-10-2013 at 08:42 AM.
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Cheers xtx thanks for info these stack up to my own stats except steyr which i wasn't sure,i said 1:16 as an average air rifle twist.Looking for 1:20 or slower to test as getting one made will probably be around £300.00.
I would also like to try a 1:20-24" barrel. I have also been looking for an Early Rapid .177 barrel (made by Anschutz) to try in my Steyr.
That way I will be able to compare a fast, medium and slow twist.
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not an answer but it helps understand what's going on
http://www.airgun.co.uk/Airgun_Accurracy.html
B.A.S.C. member
Good idea to use fast spin at same time then you can use medium as benchmark giving hopefully decent results that mean something.Hope you find one i will watch with interest.
very interesting article, although I wonder how it might be re-written in the light of Ben Taylor's smooth twist barrels which seem to achieve accuracy and adaptability to various guns with only a small section of the barrel having a twist?
They do have a twist though, with them the question is what RPM does the pellet have when it leaves the muzzle, which will give you the equivalent of a normal twist rate.
I think it's well accepted that only the last centimeter or less of the bore decides the shot, but the previous however many centimeters do decide how it arrives at that end - for instance if you use a pellet with a too small a head size it will effectively 'rattle' down the bore & it will be a lottery just how it arrives at the end, just a little but enough to widen the groups?
I'd be interested in what other people think on this, & happy to be wrong...