[Dutch4122]

I have a Ruger M-77 Mk-II in 7X57 Mauser that will not feed Remington brass reliably. When the round is pushed into the chamber it takes more force than normal to get the bolt all the way forward. The downstroke of the bolt handle requires a lot more force to push the bolt handle down.

One handloaded round using Remington brass did not eject after firing. I tapped the casing out with a cleaning rod (it came out easily and there were no pressure signs) and the rim had a groove dug into it. It appears as though the claw is not getting a proper grip around the rim.

I have tried Remington factory ammo and have gotten the same results. Federal factory ammo is also hard to chamber but doen't require as much force. Winchester factory ammo feeds like it is supposed to and will cycle without a problem as fast as I can work the bolt.

Has anybody seen this problem before? Any advice would be appreciated. I thought of just getting a big batch of Winchester brass and not worrying about it; but the stuff is almost impossible to find lately so I may just take the rifle to the gunsmith.

-Matt

 

[Jack Monteith]

Hi, Dutch:
When two makes of ammo chamber hard, I'd suspect an unsized chamber (short headspace). A gunsmith can check this with a headspace gage in a jiffy. A young friend of mine has an old Savage 110L in .270 that's short. He has to be picky about factory stuff and we stick an .006" feeler gauge under the case when we resize them.

Bye
Jack

 

[Dutch4122]

Jack-

Thanks for the info. I'll be taking it in to the gunsmith in the near future.

Just thought I'd post the question to see if this was something common to Ruger rifles.

-Matt

 

[Chief RID]

Ru7ger M77

Would a small base die be a possibility here?

 

[MikeG]

Matt,

If you find that the chamber is a bit on the short side (easy to verify with an RCBS Precision Mic and some fired brass), then you can CAREFULLY shorten a full-length sizing die. If it just needs a few thousands taken off, you can just work the die by hand on a sheet of sandpaper, backed by something flat & hard like a piece of steel or glass.

Or, find someone to stick it in a lathe a shave off a bit. I just did this for a friend - he got a die (from me!) that was a bit long and would not reliably size brass to fit in his .223 Model 7. It appears in his case that the die was the problem not the chamber.