Twist rate question

T

Travelor

New member
I have two Suhl 150-1's, both having 1:18.75 twist. One will shoot groups of about 2" at 200 yards and the other shoots patterns of 12" at 200 yards. These groups are the best I've found shooting 6 different lots of differing Eley ammo. The Suhl that shoots patterns is in a BR stock with a tuner and averages .235" ctc 5 shot groups at 50 yards and the other (the one shooting 2" groups) is in a factory wood stock and shoots almost as well at 50 yards. Obviously the twist rate appears incorrect for shooting out to 200 yards.

Why the large difference and is there anything you might suggest to improve groups at 200 yards. Our Club has a 200 yard prone match and I am the Match Director.

Thank goodness I have a Anschutz 64 MS that is shooting Eley Match EPS into 1.5" groups consistently and the wife is beating the socks off most people at the match with it.

Sorry, but I did not where else to post this question to such an august group of shooters such as yourselves.

George
 
Is this prone off a rest or with a sling? Sounds like a bedding problem on the BR. 1/18.75 mighty slow, standard is 1/16. slow twist do not seem to like cool weather ( under 65 or so) and seem to work better with the slower velocity target rounds. My1/17 sprays anything over apx 1065fps. Focus and parralex correct for distance? Do not rely on scope markings as they are just a rough guide. No Loose Screws any where in system? Stock binding On barrel? some ideas.
 
Unstable at 100 yards

You will have to try a 1- in 16 twist to see if that helps
There is a tremendous difference in group size at 100 yards with top quality
ammo.
Try other lots of ammo
A good shooting gun at 100 yards should be under 1 inch,
10 shot group
dege41
 
I have always found that I need to shoot faster ammo in my 17.5 twist Benchmark irregardless of temp. If I don't shoot over 1070 fps, it will keyhole using Eley EPS ammo. When it gets cold it becomes worse. I would suggest you try some Lapua or Eley semi auto with round nose bullets. That seem's to take care of the keyhole problems with mine.
 
Different stokes

Over the past 45 years of competition, I have found that all guns, don't shoot, all distances. If you have one that shoots well at 50 Yrds, it might not shoot worth a damn at 100 or 200 yards. I don't know what size group you need, but I'd go with the one that shot the best at 200, and tune it a bit. As for the other guns, I'd use them at the distance they're best at. If you're not happy with them, just put them up for sale, and you would be surprised, as to how quick someone will pick them up and do well with them.
 
Thanks

From what I have read above, the consensus seems to be the gun needs a new barrel with a 1:16 twist to shoot well at 200 yards.

The groups were from a benchrest with wind flags up at 100 and 200 yards.

Interestingly the best groups were with Eley Match EPS with a box velocity of 1159 fps.

I gave the gun a THOROUGH cleaning since the last range session and inpected very closely for any carbon ring (found none) or lead traces (also none found). I will give it another try Saturday morning, then retire it from the 200 yard range if no better.

BTW, we are looking to start a 200 meter BR match shooting 1/5 scale Silhouette targets. Will be interesting....................

George
 
Last edited:
George,

Have you tried any Lapua in it? May be worth a try before you scrap it.

Ken
 
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