Stiff opening bolt

[tonedaddy]

I have a custom xp-100 in 6.5 br. It has approx 250 rounds thru it. It has one problem, the bolt is always tight to open. Then is whether it is a fired round or just dry firing. The lugs look good. Any ideas here? When I say tight to open I mean I can still open it with one hand without alot of force, it just seems tighter than my other bolt actions.

 

[queen_stick]

same condition with no case at all? (simply close the bolt and dry-fire without a casing chambered).

 

[tonedaddy]

Yes, with no case at all.

 

[Sighter]

Have you dis-assembled the firing pin and checked the lubrication on the threads and cocking cam area?

 

[tonedaddy]

Yes, they look fine

 

[spclark]

Might be worth taking a Sharpie (marker) to the bolt & lug surfaces, see if you can find areas of contact that shouldn't be there.

If nothing unusual shows up, perhaps a judicious application of lapping compound to the bolt & corresponding locking lugs (with a few slow cycles of opening / closing) would help reduce what extra friction there is?

How does this bolt handle compare to your other bolt actions, as to effective length? Do XP-100's have shorter bolts than similar actions used in rifles?

 

[tonedaddy]

I have 3 other xp-100's and they are smooth as silk.

 

[rayjay]

Remove the firing pin assy and put the bolt back in and see how it feels. It should open and close and slide back and forth with basically no effort. If it doesn't then you need to find the area that the bolt is binding against.

You could then swap the firing pin assy with one of your other actions and see if the lift is improved. If it is then disassemble the original fp assy and see if the firing pin is bent or has other issues.

I have seen the tag end of the firing pin spring be deformed and dragging against the shank of the FP.

I have seen very rough cocking ramps.

Every cocking piece I have seen have tool marks on the nose that bears against the cocking ramp.

 

[Rustystud]

Check the following:
The front of the XP-100 action is very thin compared to a Remington 700. See if the front action screw is rubbing the bolt.
Nat Lambeth

 

[kevinthree]

You mentioned it was a "custom" action. This problem may be caused by over lapping of the lugs that effectively moved the cam surface on the bolt handle away from the cam surface in the action. This is very common and is always the first thing to inspect when buying an used Rem. 700. If the cam surface on the bolt handle is tortured- keep looking.

Kevin
Ole's gun shop

 

[Kings X]

Remove the firing pin assembly and try.
Also check length of front (only) guard screw.

 

[tonedaddy]

Thanks for the replies, I took the bolt apart & cleaned and greased it. Problem solved!

 

[spclark]

You didn't grease the firing pin & spring did you?

I'd have to think that not a good idea when you're looking to minimize lock time / maximizing firing pin impact force...

 

[tonedaddy]

just here>Have you dis-assembled the firing pin and checked the lubrication on the threads and cocking cam area?

 

[spclark]

Sounds good.

Some folks apply grease to parts that were never intended to receive it, then wonder why things don't work better than they used to: more is better is not a universal rule of thumb.