Potential Problem with Rem 7400

[Old Ranger]

A club member was at our range yesterday. He was sighting in a used Rem 7400 he had just bought. Winchester factory ammo. Primers on several fired cases where slightly flattened and cratered. One had a primer which had backed out significantly.. No sign of case stretching.
if I remember correctly I was once told that Rem 742/7400's can develop headspace problems through usage.

Any ideas on what's going on here?

 

[nomad 68]

A lot of them don't do well with Winchester ammo. Is it clean?that sounds like more of an ammo issue to me and winny ammo is not immune to problems as of late.

 

[maynard]

Federal ammo?

 

[gunpro]

try different ammo. there is so much inconsistency with some factory ammo nowadays. if you get the same issue with different brands or loads then take it to your local gunsmith to get it checked out.

 

[gunrunner100]

7400s and 742s share a similar look but the bolts are different between the 2. I would tend to agree with the responses you have received so far about trying different ammo first. Headspace can be checked if the problem persists but all that will do is confirm excessive headspace. Reloading could help that problem.