Joined
·
2,846 Posts
Ripsaw, excelent point that I had not thought of . . . . at last count I have 16 lbs of IMR4895 and 8 lbs of RG4895 pulldown powder . . Was hoping to not buy any more for awhile . . GI8dance2GI8dance2GI8
HELP!! Bush Rifle Shoots Like KRAP!!
21 - 36 of 36 Posts
Joined
·
1,863 Posts
Well, the goal is to get the heel down so the barrel's front band lip will go up, creating the tension at the ferrule. In addition, with the heel clamped to the stock another friction point further back is created which further stabilizes the action's position in the stock. I think shimming under the heel would tend to defeat that.
What comes to mind is a quick and dirty method to see if getting the heel down will get the barrel up. If you have a furniture clamp, such as http://www.harborfreight.com/24-inch-ratchet-bar-clamp-spreader-46809.html , you can clamp the heel tightly to the stock without damaging either and see if you get tension at the stock ferrule. You can even do this without the trigger group installed. If that works, then the shims between the trigger group and the stock should do the trick. If it doesn't, then shim the fulcrum area under the scope mount and try the clamp trick again. Also note that aluminum soda can material is pretty thin (I think about .005") so it'll take a few layers to pull the action into the stock using the trigger group. You might try bending them accordion style so the layers will stay together.
Down the road, if you find a trigger group/stock combination that gives you a really tight lockup without the help of shims, you can use the furniture clamp instead of the trigger guard to close up the gap and then just close the trigger guard to lock everything in place. That way, you reduce stress and wear on the trigger group but still get a good tight lockup.
Joined
·
11,160 Posts
Unless you get tension up front along with good groups and the heel is still not touching the stock, which is what happened to me.
Joined
·
1,863 Posts
I was figuring that with the .050" gap between the front band lip and the ferrule up front and only a .020" gap at the heel, the heel gap would close up first.
On the other hand, I too have a situation where there's a slight gap at the heel but there's tension up front and the rifle shoot better than it ever has.
Joined
·
11,160 Posts
Not trying to cause any friction, just saying what I did with mine and it seems to work. I'm no expert, I'm just an amateur and I just relate what it is I have done. When it comes to troubleshooting rifle problems I wish I knew a lot more than what I do know.
Joined
·
1,863 Posts
No friction at all because I agree with you since I have the same condition you do on one of my M1A's and got the same benefits.
One of the many advantages of TFL is that with a lot of members, there's a lot of experience to draw on and a lot of contributions to make; the M14 is complicated and the interactions among its parts can be subtle, so the more eyes and ideas on the problem, the better off we all are.
Joined
·
11,160 Posts
Yup, that's why I love this site, if I don't know then somebody else usually does.
Joined
·
2,846 Posts
Just so we are clear . . the .050 clearance is between the Vertical surfaces, i.e.; the front face of the ferrule and the back side of the watchamacallit that has the lip on it. There is tension on the band . . takes three fingers to squeeze the tension out . .
I tried a double thickness of a soda can on the three trigger tabs and it does take the heel of the reciever down to the stock, but the stock is not perfect so the heel rests on only one side. . .
I'm wresting with the FH now so I can shim the gas cylinder . . .
Joined
·
1,863 Posts
Thanks for the clarification on the .050" gap between the front band and the ferrule.
Someone's going to have to help me out here because I don't remember the details but I believe there was a TFL thread about some SAI receivers which were made in such a way that they didn't sit squarely on a typical stock...
Sounds like you've got good tension between the front band lip and the ferrule.
Joined
·
226 Posts
My situation exactly
I'll throw in, as I'm in the same boat. With my BNIB SAI scout, I got a 4.6" group with AmEagle OTM. I'm also shooting 150 FMJBT (hornady with the jacked up cannelure), IMR 4895, still working up loads. HOWEVER, I'm a noob to the platform, you may not be.
Mods: shimmed GC(lots of slop in the front band before), TiN piston, Sadlak NM spring guide. I also played with the overall length of the projectile. First reload progression I set to the cannelure (~2.70), second set of reloads I let out to about 2.79 ignoring the cannelure.
This weekend I warmed up with Black Hills 168gr Match since I couldn't find any AmEagle for a match ammo comparison after the rifle mods. Groups improved only slightly to 3.7"
I don't have the data in front of me, but the first round of reloads set to the cannelure didn't improve my attitude any. The second set with the longer oal did. My best group was a 3.3" group with 40.5 gr. Not great but improving, I can keep them all in the black now.
I'm sure there is some "seasoning" of the barrel and my skills attributing to the improvement, so take the data FWIW. Lots of changes at the same time. I'm not sure if my rilfe has the stock fit issues yours does, it has a horseshoe mark on the stock where the heel sits down, and there is now pressure between the band and ferrule (how much I can't tell you). I'm also not sure if the trigger group has the appropriate lock down pressure, again being new to the platform. Not sure any of this helps, but I figured misery loves company. Keep us posted.
I'll throw in, as I'm in the same boat. With my BNIB SAI scout, I got a 4.6" group with AmEagle OTM. I'm also shooting 150 FMJBT (hornady with the jacked up cannelure), IMR 4895, still working up loads. HOWEVER, I'm a noob to the platform, you may not be.
Mods: shimmed GC(lots of slop in the front band before), TiN piston, Sadlak NM spring guide. I also played with the overall length of the projectile. First reload progression I set to the cannelure (~2.70), second set of reloads I let out to about 2.79 ignoring the cannelure.
This weekend I warmed up with Black Hills 168gr Match since I couldn't find any AmEagle for a match ammo comparison after the rifle mods. Groups improved only slightly to 3.7"
I don't have the data in front of me, but the first round of reloads set to the cannelure didn't improve my attitude any. The second set with the longer oal did. My best group was a 3.3" group with 40.5 gr. Not great but improving, I can keep them all in the black now.
I'm sure there is some "seasoning" of the barrel and my skills attributing to the improvement, so take the data FWIW. Lots of changes at the same time. I'm not sure if my rilfe has the stock fit issues yours does, it has a horseshoe mark on the stock where the heel sits down, and there is now pressure between the band and ferrule (how much I can't tell you). I'm also not sure if the trigger group has the appropriate lock down pressure, again being new to the platform. Not sure any of this helps, but I figured misery loves company. Keep us posted.
Joined
·
2,846 Posts
Hey stevelish, thanks for the post. Those FUBAR Hornady 150s with the farked up canelure shoot good in my Garand and M1A NM . . I seat them to 2.800 and ignore the canelure . .
I would be happy with a frikkin ROUND 3" group . . I get fliers mostly at the 2:00 position out to 5" to 6"
I have not tried match ammo yet . . I am not a total noob to the platform . . but I AM an engineer and I do tend to over-analyze and expect alot . . . . . . I enjoy getting a rifle to shoot. I worked a Mini 30 till it was a 1.5 moa rifle . . some people said it was polishing a turd, but I enjoyed the challenge . . .
Same Exact Issues
Glad I found this thread. I am in the exact place Locutus is in. Bought a lightly used (200-300 rounds) M1A and after waiting 20 years to find one when I had the money available, but was more than a little disappointed when I found it will only group 5-6" at 100yds. This is with Federal GMM and 4 different handloads.
Looks like the trigger was left locked in the stock (no tension), so I was going to try swapping stocks with a friend who has a new synthetic stock model. I also ordered a set of Smith gas cylinder shims.
I have been really frustrated to not get it to group, but want to thank the group for sending me in the right direction.
I see more range experimentation time in my future.
Glad I found this thread. I am in the exact place Locutus is in. Bought a lightly used (200-300 rounds) M1A and after waiting 20 years to find one when I had the money available, but was more than a little disappointed when I found it will only group 5-6" at 100yds. This is with Federal GMM and 4 different handloads.
Looks like the trigger was left locked in the stock (no tension), so I was going to try swapping stocks with a friend who has a new synthetic stock model. I also ordered a set of Smith gas cylinder shims.
I have been really frustrated to not get it to group, but want to thank the group for sending me in the right direction.
I see more range experimentation time in my future.
Joined
·
2,846 Posts
dmack; check out the happy ending in The Firing Line forum above under "Range Report . . Remember that Bush Rifle That was Not Shooting Well ? ."
oh, and don't feed the troll there . . .dance2
Joined
·
2,520 Posts
Group
Dmack, you might want to take your action out of the stock and look at the bottom of the stock ferral in the front, if the barrel harmonics are causing it to whip around and hit the metal ferrel piece, it will leave shiny marks and throw the settling place of the barrel in a different spot each time, hence the different groups. Mine was rubbing badly and I had a flyer, so I took a chain saw file and cleaned it up and marked with black marks-a-lot.....reinsert and shoot again.....check again, if it is rubbed off, take more meat off. There is a thread about a national match modification that requires removing the entire inside part of the metal on the ferrel and leaving just the wood. If the wood is rubbing still, hull it out some until the barrel is uninterupted in its star shaped harmonic whipping action. Also check the sides at the end of the stock, some will exhibit being hit and show smashing of the wood, hull it out to give a good 1/8" clearance. Do this and check the fit of receiver and barrel band pressure and I feel confident that the groups will shrink to acceptable levels.
Dmack, you might want to take your action out of the stock and look at the bottom of the stock ferral in the front, if the barrel harmonics are causing it to whip around and hit the metal ferrel piece, it will leave shiny marks and throw the settling place of the barrel in a different spot each time, hence the different groups. Mine was rubbing badly and I had a flyer, so I took a chain saw file and cleaned it up and marked with black marks-a-lot.....reinsert and shoot again.....check again, if it is rubbed off, take more meat off. There is a thread about a national match modification that requires removing the entire inside part of the metal on the ferrel and leaving just the wood. If the wood is rubbing still, hull it out some until the barrel is uninterupted in its star shaped harmonic whipping action. Also check the sides at the end of the stock, some will exhibit being hit and show smashing of the wood, hull it out to give a good 1/8" clearance. Do this and check the fit of receiver and barrel band pressure and I feel confident that the groups will shrink to acceptable levels.
21 - 36 of 36 Posts
