I have an M1 carbine barrel that's been abused in its former life, and now the POI drops by approx. 4 MOA after the first eight rounds or so. Is there anything I can do to the barrel to stop this from happening? It's sorta sudden - everything groups nicely, then all of a sudden the POI drops and a new group starts 4 MOA lower.
POI drops as barrel heats up
- Thread starter Plinker
- Start date
Does your barrel have the front barrel band bayonet fitting. They were supposed to stiffen the barrel and improve accuracy. Just something I read. If you do have one installed and it is not working, maybe you could remove it and install a barrel band without the bayonet lug and see if it makes any difference before going to more drastic measures like a new barrel.
Yeah -I had a type-2 band, but I changed it to type-3 with the bayo lug. I also hammered on the recoil plate to increase tension on the action when in the stock. Neither made any difference.
The bore and muzzle are in great shape on the barrel, so I'm reluctant to swap it out.
Iron sights or glass on the carbine??
2 distinct groups sounds more like a scope/mount issue rather than with the barrel or bedding. Barrel shifting due to heat usually shows as vertical or horizontal stringing.
2 distinct groups sounds more like a scope/mount issue rather than with the barrel or bedding. Barrel shifting due to heat usually shows as vertical or horizontal stringing.
Mystic Precision
CGN Ultra frequent flyer
- Location
- Summerland, BC
You have one of the very rare experimental full auto fire barrels.
After the first burst (6 to 8 rds), the barrel 'adjusts' for muzzle climb allowing the shooter to keep continuous auto fire on target.
At least, that would be my story to the collector willing to pay you amazing dollars for such a rifle
Jerry
After the first burst (6 to 8 rds), the barrel 'adjusts' for muzzle climb allowing the shooter to keep continuous auto fire on target.
At least, that would be my story to the collector willing to pay you amazing dollars for such a rifle
Jerry
You have one of the very rare experimental full auto fire barrels.
After the first burst (6 to 8 rds), the barrel 'adjusts' for muzzle climb allowing the shooter to keep continuous auto fire on target.
At least, that would be my story to the collector willing to pay you amazing dollars for such a rifle
Jerry
Jerry - you actually had me going there!
In response to 'Boo, it's got a red-dot sight on it. It has crossed my mind that it might be the sight, but it worked fine on the last gun it was on. I'll do a (very) slow-fire test this weekend, and see if the secondary grouping vanishes. If not, I'll swap out the sight and see what happens.
Does the new band you put on contact the top of the barrel? If it does it might be worth while relieving it slightly. A bit of heat expansion in the barrel and increased pressure against the band? Barrels normally shoot away from hard contact. In this case it might be down.
