OK folks I'm here seeking advice again ;D.I have built a 30BR with a winchester m70. the gun performs well but I think it needs some tweeking.Here's my question,should I have the firing pin bushed and is there anything else that I should do to the bolt while the gunsmith has it that will help or improve it's performance?The action has been trued it is in a hs presision stock with a bedding block and stock has been opened up for barrel.I know some folks say building a target gun with a factery action is a waste of time but I just couldn't afford a custom action.I have tried several different custom bullets and the 7 ogive 118gr seem to be what the gun likes.I don't have any trouble getting the 10 ring I just can't get the x for some reason.Any help you folks can offer will be greatly appreciated. Sorry I forgot to include these spec's.Barrel is a 1in17 twist 22 inches long I have been using the loads off of this sight which is 34.7gr of h-4198 and seating bullets at the lands.
30BR questions
- Thread starter fatalbert
- Start date
Some more info on your load and the twist/contour of your barrel may be helpful.
Well..there is a lot to fine tuning a 30BR...first you load is irrelevant..what is the velocity over a chronograph???
The sweet spot (node) is at 2970-2985 fps..neck tension on the brass should be experimented with more or less..change bushings once velocity is located..seating depth is going to be somewhere in the jam, but too much will cause vertical..start long and go shorter about .003" increments until the groups get round or flat...also move your rifle forward on the front rest/bag to help balance the rifle..it will also remove some of the vertical...and next time trade your M70 Win action for a Remington before trying to build a BR rifle...
The sweet spot (node) is at 2970-2985 fps..neck tension on the brass should be experimented with more or less..change bushings once velocity is located..seating depth is going to be somewhere in the jam, but too much will cause vertical..start long and go shorter about .003" increments until the groups get round or flat...also move your rifle forward on the front rest/bag to help balance the rifle..it will also remove some of the vertical...and next time trade your M70 Win action for a Remington before trying to build a BR rifle...
fatalbert said:
Ok, was the action 'glass-bedded' to the block? If not, I'd start with a nice 'paint'coat' bedding job . . . and make certain that, with the action installed, the screws do NOT contact the block screw-holes. Very few commercial actions are ROUND - if not 'trued' on the outside, even with a bedding-block, this can cause bedding (stress) problems. And sometimes, the rear recoil-lug-face does not even contact the front-face of the bedding-block! Rather, the action-screw(s) make contact on the block-holes, thus holding the recoil-lug away from the block-face!
The latter is never a good thing. It's possible that your smith will check these attributes - make certain he does. Good shootin'! 
RG
I think Randy hit the nail on the head. If the rifle isnt beaded all else is irrelevant. I have an HS stock with a predator action un beaded. I know first hand that even a close fitting action isnt as accurate as a properly beaded action. Until you can take away the obvious, there no point looking anywhere else. Save up a couple hundred bucks and get the rifle beaded, then go from there. Lee
Make sure your windflags are super responsive.
Once you get the rifle really shooting decent then it's flag reading that gets you good X count. You also have to know if there are specific conditions at your range that affect the bullet flight. Like at my range a 6:00 [ tail ]wind will cause the bullet to hit low whereas it should hit high. Our bench roof has a baffle that acts like the flaps on an aircraft wing.
Another hint is to really be sure that you know where the scope zero is. This can really bite you going from 100 to 200 during a match on a windy day [ or vice versa at our range, we shoot 200 first ]. I like to have my POI at 12 o'clock. Say we happened to get a 'no wind' condition going . If I held on the dot the bullet would hit on the 10 ring at 12 o'clock. To hit the dot I would hold at 6:00 on the 10 ring.
If I have a slight wind from the left to the right [ a green condition ] I would hold opposite the flag vane , ie 7:00 but a little low . A slight orange [ from right ] condition I would hold at 5:00 low.
Once you get the rifle really shooting decent then it's flag reading that gets you good X count. You also have to know if there are specific conditions at your range that affect the bullet flight. Like at my range a 6:00 [ tail ]wind will cause the bullet to hit low whereas it should hit high. Our bench roof has a baffle that acts like the flaps on an aircraft wing.
Another hint is to really be sure that you know where the scope zero is. This can really bite you going from 100 to 200 during a match on a windy day [ or vice versa at our range, we shoot 200 first ]. I like to have my POI at 12 o'clock. Say we happened to get a 'no wind' condition going . If I held on the dot the bullet would hit on the 10 ring at 12 o'clock. To hit the dot I would hold at 6:00 on the 10 ring.
If I have a slight wind from the left to the right [ a green condition ] I would hold opposite the flag vane , ie 7:00 but a little low . A slight orange [ from right ] condition I would hold at 5:00 low.
Gentalmen; I would like to thank all of you for you help,I have never been involved in a sport where the competitors so freely share their information and are so open to helping other competitors become better at their sport.I would like to address the gentalman who suggested the next time I build a custom caliber gun to sell my winchester and use a remington,to this I respond, I have a friend who was a sniper in vietnam and his advice to me was to use the winchester because of his exsperience with them in that arena. I figured a man trusted his life to one, it was good enough for me.Randy and Joe I am specially honered by your responses, I don't know of another sport were two world class performers would offer advice and help to someone they didn't know and had never met.It makes this 56 yr old mech proud to be involved in such a sport, thanks again for all the help!
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