Hard chambering on new custom rifle

M

merbeau

New member
Hi

I have just finished building a custom 6.5 Swede off a Remington 700 LA that was originally in 30-06 caliber. I purchased a new custom PTG stainless bolt, a new Oberndorf stainless trigger assembly, new stainless follower, and follower spring.

After assembly I then inserted a dummy round into the magazine and when I tired to chamber the round it was extremely difficult. Tried polishing the follower with no luck.

I should mention I use Nosler brass which has a slightly larger rim than brass made by Winchester, etc.

Anyone have any suggestions of how to make the action smoother or is it just time as parts start to 'wear in'.

Thanks

Robert
 
On a recent re barrel of my 223, I was getting set to load some ammo for load work up. The empty brass chambered, but the loaded round would not fully chamber. After much work and frustration, the problem was the match chamber. The neck was so tight that anything bigger than .247 wouldn't fit. The Lapua brass had neck wall thickness above the usual. The gun is back at the smith to open up the chamber neck.

See if a factory round will chamber. If so, compare measurements between factory and reloads. That will tell you where the problem is. That's what I finally had to do. Luckily a neighbor had a factory 223 round.
 
After assembly I then inserted a dummy round into the magazine and when I tired to chamber the round it was extremely difficult. Tried polishing the follower with no luck.
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After
Hi
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I expected "I purchased a barrel chambered to 6.5mm55 Swede". After receiving the barrel and before you installed? it I expected you to say something about checking the chamber. I am sure I have a 6.5mm55 head space gage but I do not shoot gages, I shoot ammo, so I would have checked the chamber in the barrel for case head protrusion. I have new/factory 6.5mm55 ammo. I have R-P 6.5mm55 fired cases and I have a few rounds of 6.5mm55 rounds I have loaded.

After checking the barrel for case/round fit I would have measured the receiver. After measuring the receiver I would have finished reaming the chamber if necessary. there is nothing entertaining about a tight chamber. I can tighten the chamber with big-O-cases and thicker necks.

Not sure what I am going to do with it but I have a Karl receiver chambered to 6.5mm with a 308 case body.

F. Guffey
 
Additional Information

The issue is PRIOR to the round going into the chamber. A factory round chambers just fine as does my reloads when just one round is shot at a time. That is how I have been shooting the rifle while breaking in the barrel and my initial tests with various powders.

Only in the last week when I decided to place several rounds in the magazine that the problem arose. To initiate the first round to the chamber from that position requires a good hard push to start the round moving. Much harder than my other rifles.

Hope that clarifies the problem.

Thanks

Roibert
 
Only in the last week when I decided to place several rounds in the magazine that the problem arose. To initiate the first round to the chamber from that position requires a good hard push to start the round moving. Much harder than my other rifles.
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The Remington is push feed. Loading one at a time without resistance to bolt closing eliminates the tight chamber as suspect. Now you start on the problems of moving/stripping ammo from the magazine.

F. Guffey
 
Additional testing

The follower is in the right direction. Tried several experiments.

Experiment one: I switched out the new follower with the old follower. Same difficulty.

Experiment two: Switched out the new follower spring with the old spring same problem.

Experiment three: Switched out new follower spring with old spring and old follower same problem.


That appears to eliminate the new follower spring and follower as the problem.

NEXT: The PTG replacement bolt was ordered 0.005 larger than the old bolt by the smith who did the work. The bolt is very tight fitting.

So my conclusion is that the bolt is causing the problem and will need to be broken in further. Reasonable?
 
I dunno, .005 is almost nothing. How does it feel feeding after the first round is gone? Excuse me if you explained that and I missed it.
 
Progress

Gun Plummer

Yesterday I moved the bolt very slowly from front to back in increments. For example, from the locked position open the bolt and move it back perhaps an inch. Then try to close the bolt looking for resistance. Repeated this procedure until the bolt was at it maximum extended point at the back of the receiver. When the bolt was at it farthest point all the way in back of the receiver when starting to move it forward there was resistance.

I sat in front of the tv last night just cycling the bolt back and forth from the back position for about 30 minutes. I then placed four dummy rounds into the magazine well. I then attempted to cycle the first round into the chamber and it went in with much less difficulty than previously. The round ejected without problem. The second round went in with a little more resistance but still nowhere near what I was experiencing. Same for the third and fourth. So perhaps a few more cycling efforts will make the feeding problem easier.

Thanks

Robert
 
It's an obvious question that I'm sure you already looked at...
But given that it's a new PTG bolt, any visible machining marks still on it that would need to be lapped out?
 
Old bolt/new bolt experiment

...But given that it's a new PTG bolt, any visible machining marks still on it that would need to be lapped out?....

That gave me an idea. When I sent the receiver to the smith I kept the original bolt. It was stored in a drawer in my reloading table. I removed the new bolt and replaced it with the old bolt. Placed 3 dummy rounds in the magazine and had no problem cycling the action smoothly.

It appears the lugs are tighter fitting on the new bolt then on the OEM which probably is due to the bolt being ordered larger than normal. The milling from PTG is smooth with no visible marks showing.

Would placing lapping compound on the lugs and cycling the bolt back and forth on the rear end of the receiver help? Any other suggestions?

Thanks
Robert

PS can not use the old bolt because it was headspaced for a 30-06.
 
which probably is due to the bolt being ordered larger than normal.
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Lost me there. What was "larger than normal", and why?

So you're saying PTG did this custom, and to your specs?

In any case, I wouldn't lap them in the receiver as you'll cut a groove inside it for the lugs- you want to lap the side of the lugs only (it sounds...) and not the receiver raceway.
 
I tried to tighten an Arisaka bolt/receiver like that once. I was making a new bolt anyway. I think I think I made it about .015-.020 bigger. It got stuck at the receiver ring. The receiver ring was slightly smaller than the bore through the receiver bridge. Now that you narrowed it down to the bolt, I would put take a felt tip marker and see just where it is hitting. I don't know, is every outer dimension on the bolt larger, or just the main body?
 
"So my conclusion is that the bolt is causing the problem and will need to be broken in further. Reasonable?"

Or thread the factory bolt for whatever knob you want and return the PTG bolt.

Jim
 
Thanks for the advice

I cannot send the PTG bolt back since it was a custom order. The bolt was ordered at 0.7000 OD which is slightly larger than the old bolt 0.6995 based on the smith asking me if the old bolt ‘rattled’ which it did so he suggested that I order the upper end of the OD diameter. I am assuming the main body is what is slightly larger.

The old bolt would have to be headspaced and it is also in bad shape with pitting.

So if lapping the lugs inside the receiver is not a good idea how do you lap just the lugs?

Thanks
 
Mic how the thick the lugs are. Then mic across the to lugs. Compare to the old bolt. If I am reading that correctly, there is only 5 tenths variation between the two bolt body diameters. A receiver with tolerances that tight would be rare IMO. Some where there is a major difference in the bolts.
 
^^
This is what I was thinking as well, perhaps there was a machining error- especially given that it wasn't their typical CNC run 700 bolt.
 
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