bolt overriding rounds

Fleet · March 4, 2013, 06:43 PM

I've got a Rem 700 in 7mm Rem Mag. When closing the bolt, more often than not the rounds will feed part way out of the mag and then the bolt will override the case head. Any ideas what could cause this?

dahermit · March 4, 2013, 07:43 PM

As I remember, the Remington 700 is a push-feed system. That means the round must pop-up completely loose from the rails (where as a controlled feed system the extractor "captures" the round before it is released by the rails), in order for the bolt face to push it into the chamber. Try watching as you slowly push the bolt forward...at some point, the round should pop-free of the rails. If it does not, the bolt will ride over the round and jam. Note: a rail problem is more likely with a new gun. If this is an old gun that just started having this problem there are other considerations. Are you shooting hand loads or factory? If neck-sized hand loads, the bodies of the cases are slightly larger in diameter than factory, and could be causing some binding in the magazine.

Fleet · March 4, 2013, 10:58 PM

This is a factory original rifle, shooting factory loads. In going slowly, the 2nd round isn't coming free of the rails, and is being trapped by the bolt and the feed ramp.

dahermit · March 4, 2013, 11:29 PM

Quote:

This is a factory original rifle, shooting factory loads. In going slowly, the 2nd round isn't coming free of the rails, and is being trapped by the bolt and the feed ramp.

If it is a brand-new rifle (as opposed to one that fed alright until recently), I would suspect that the inside of feed rails need smoothing. If you have metal working skills/experience you could do it yourself. However, a gunsmith is always a good idea.

Fleet · March 4, 2013, 11:31 PM

Definitely not a new rifle.....70's production. I'll stone the rails a bit and see what happens.

Bart B. · March 5, 2013, 07:41 AM

The first thing I'd check is the hardware that pushes the rounds to the top of the box magazine. Both the follower and its spring need to be free of any binding.

With an empty magazine, does the follower press easily all the way down and come back up when released?

Are the sides of the magazine inside walls and the follower free of corrosion and very smooth?

Is the follower spring weak?

Is the follower spring bent such that pressure on the follower's not keeping the same force on both ends of it?

Sport45 · March 5, 2013, 07:44 AM

Did it work before? If it did then it probably doesn't need any sanding.

dahermit · March 5, 2013, 09:09 AM

Quote:

The first thing I'd check is the hardware that pushes the rounds to the top of the box magazine. Both the follower and its spring need to be free of any binding.
With an empty magazine, does the follower press easily all the way down and come back up when released?
Are the sides of the magazine inside walls and the follower free of corrosion and very smooth?
Is the follower spring weak?
Is the follower spring bent such that pressure on the follower's not keeping the same force on both ends of it?

All good advice. All should be done before altering the feed rails (polishing, smoothing).

March 4, 2013, 06:43 PM	#1
Fleet Senior Member Join Date: December 1, 2011 Posts: 108	bolt overriding rounds I've got a Rem 700 in 7mm Rem Mag. When closing the bolt, more often than not the rounds will feed part way out of the mag and then the bolt will override the case head. Any ideas what could cause this?

March 5, 2013, 07:44 AM	#7
Sport45 Senior Member Join Date: May 25, 1999 Location: Too close to Houston Posts: 4,196	Did it work before? If it did then it probably doesn't need any sanding. __________________ Proud member of the NRA and Texas State Rifle Association. Registered and active voter.

March 4, 2013, 07:43 PM	#2
dahermit Senior Member Join Date: October 28, 2006 Location: South Central Michigan...near Posts: 6,501	As I remember, the Remington 700 is a push-feed system. That means the round must pop-up completely loose from the rails (where as a controlled feed system the extractor "captures" the round before it is released by the rails), in order for the bolt face to push it into the chamber. Try watching as you slowly push the bolt forward...at some point, the round should pop-free of the rails. If it does not, the bolt will ride over the round and jam. Note: a rail problem is more likely with a new gun. If this is an old gun that just started having this problem there are other considerations. Are you shooting hand loads or factory? If neck-sized hand loads, the bodies of the cases are slightly larger in diameter than factory, and could be causing some binding in the magazine.

March 4, 2013, 10:58 PM	#3
Fleet Senior Member Join Date: December 1, 2011 Posts: 108	This is a factory original rifle, shooting factory loads. In going slowly, the 2nd round isn't coming free of the rails, and is being trapped by the bolt and the feed ramp.

March 4, 2013, 11:31 PM	#5
Fleet Senior Member Join Date: December 1, 2011 Posts: 108	Definitely not a new rifle.....70's production. I'll stone the rails a bit and see what happens.

March 5, 2013, 07:41 AM	#6
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	The first thing I'd check is the hardware that pushes the rounds to the top of the box magazine. Both the follower and its spring need to be free of any binding. With an empty magazine, does the follower press easily all the way down and come back up when released? Are the sides of the magazine inside walls and the follower free of corrosion and very smooth? Is the follower spring weak? Is the follower spring bent such that pressure on the follower's not keeping the same force on both ends of it?