Correct Rimfire Rifle Torque Specs

[Willy]

I'm in the process of playing with my B-mag to see if I can improve the groupings. As a result I removed the stock and before I assembled it I googled the torque settings for the B-mag; one Savage site listed the torque settings for all Savage rimfires at 15 in lb, but the B-Mag Manual lists the torque at 40 in. lb. That is a significant difference; which one is correct? Fifteen in lb is not very much, just a little more than finger tight. (My apologies if this has already been discussed in another thread, I did search for one but didn't come up with anything.) I was thinking of taking the B-Mag to a gun shrink, it may be schizophrenic...

[LoneWolf]

15in lbs is probably plenty for a rimfire. One of the tricks used to help with tunning a rimfire since ammo cannot be reloaded to a specification that the rifle likes is to tune the action screw torque setting. sometimes the right adjustments can tighten up groups in some rifles. The action screws should be rated beyond 40in lbs with that figure being about the max torqure you should apply.

Also take into account that for year "tight" was what felt tight enough to the user. I prefer to use a torque spec simply because I tend to strip and break screws all the time when I don't!

[SavRimfire]

15in lbs is probably plenty for a rimfire.

I prefer to use a torque spec simply because I tend to strip and break screws all the time when I don't!

All my rimfires shoot their best at 15-18in lbs and I, always, use a torque wrench because I too have had a, VERY, bad habit of over tightening things and either stripping them out or breaking them off. Once I started using a proper inch lb torque wrench, I quickly realized just how much I was OVER tightening the actions. Rimfire actions aren't nearly as robust as a centerfire action and I only use 30-35in lbs on those.

I believe a lot of the flyers and or poor accuracy associated with the Bmags was due to over tightened actions. I know in my HB SS Bmag as I tightened the screws above 20in lbs the accuracy quickly went to sheet and at 30in lbs and above, the pattern looked like it had been shot with a shotgun.

[Willy]

Well, I tried almost everything with my straw-stock, pencil-barrelled B-Mag, to improve accuracy. Nothing seems to work: 15 in lb to 30 in lb on the stock screws doesn't change anything, several rubber strips inside the stock, O rings located every which way on barrel, different ammo etc etc etc. All this effort on the B-Mag has led me to one inescapable conclusion:

The B-Mag is an experiment conducted by the CIA to determine how long it would take to drive the average gun nut around the bend.