PMR Pro 2 issue after dry fire

[bf2junky]

I'm not exactly sure how to describe the issue I'm experiencing. I have a brand new MPA PMR Pro 2 chambered in 6.5CM with no rounds fired. I've had the the bolt out of the rifle for a few days while I was working up a new seating depth for load development. The only thing that I've put in the chamber is a Hornady modified case and some Lapua brass.

I put the firing pin back in the bolt and function tested the rifle. It now is extremely hard to lift the bolt after dry firing. It sounds like the firing pin spring is binding up or something. I'm not sure if it is an issue with the Triggertech Diamond trigger either. I do not remember it being like this when I first got it so I'm not sure what could of happened with the bolt and firing pin just sitting on my bench.

Here is a video. If you need other photos of anything just holler.

 

[D R A K E N B U R G]

Can you share a pictures of the following:

• A photo of the bolt removed from the rifle, with the sear in the fired position. Share a detail photo of the sear area. I want to make sure that the stiker is bottoming out on the striker front shoulder and not the cocking piece.
• A photo of the stiker assembly removed to ensure everything is in place, especially around the sear area.

Hope we can help you out.

 

[bf2junky]

Can you share a pictures of the following:

• A photo of the bolt removed from the rifle, with the sear in the fired position. Share a detail photo of the sear area. I want to make sure that the stiker is bottoming out on the striker front shoulder and not the cocking piece.
• A photo of the stiker assembly removed to ensure everything is in place, especially around the sear area.

Hope we can help you out.

Gotcha, sounds like you are requesting to have the trigger pulled from the action? I'm awaiting a response from MPA to see what they say. I may end up having to pull it and also wondering if cleaning the trigger out with some lighter fluid might help function?

 

[spife7980]

Sounds dry as a bone, lube it. Cant really tell that anythings wrong with it other than being a heavy three lug.

 

[bf2junky]

Sounds dry as a bone, lube it. Cant really tell that anythings wrong with it other than being a heavy three lug.

I've greased the bolt pretty liberally with TW-25B but I guess with it being new it is absorbing it. I will put flush the trigger with lighter fluid tomorrow when Amazon brings my Zippo fluid. I hope the lighter fluid does the trick...

 

[D R A K E N B U R G]

Gotcha, sounds like you are requesting to have the trigger pulled from the action? I'm awaiting a response from MPA to see what they say. I may end up having to pull it and also wondering if cleaning the trigger out with some lighter fluid might help function?

No, just photos of the striker assembly and also a photo of the cocking piece in the bolt in the decocked position to see if the cocking piece is bottoming out on the cocking ramp.

 

[Drew M]

Since this only started since you had the bolt apart, I would think it might be a good idea to pull it down again to check that everything is in the right place/order.

 

[Mike Casselton]

Sounds dry as a bone, lube it. Cant really tell that anythings wrong with it other than being a heavy three lug.

I'm with Spife on this one.
Did you wipe all of the lube off of the bolt lugs and cocking cam?

Put a tiny dab on them and try it again

 

[bf2junky]

I relubed everything. I'm not sure what you mean by the bolt being in the decocked position. I'm pretty certain the bolt is put together properly. It really only goes together one way. Everything feels fine until I dry fire and try to lift the handle. Here are some pics, let me know if these are wrong.

 

[carbonbased]

Do you have another trigger to test with?

Is the front of the bolt handle rubbing on the chassis? Doesn’t really look like it, but…

I know your rifle is brand new & never fired, but I found this post sort of interesting (slightly bent firing pin): https://rokslide.com/forums/threads/tikka-hard-bolt-lift-after-dry-firing-wtf.257194/post-2881218

Did you drop the firing pin? Sorta last ditch idea here.

 

[bf2junky]

Do you have another trigger to test with?

Is the front of the bolt handle rubbing on the chassis? Doesn’t really look like it, but…

I know your rifle is brand new & never fired, but I found this post sort of interesting (slightly bent firing pin): https://rokslide.com/forums/threads/tikka-hard-bolt-lift-after-dry-firing-wtf.257194/post-2881218

Did you drop the firing pin? Sorta last ditch idea here.

Don't have another trigger. Firing pin was never dropped, literally sat in one place for a few days. The bolt shroud did get turned into that channel that make the firing pin protrude and I had to reset that. Didn't seem like a big deal according to this video:



Other than that it has been sitting there...going to read that thread.

 

[spife7980]

I've greased the bolt pretty liberally with TW-25B but I guess with it being new it is absorbing it. I will put flush the trigger with lighter fluid tomorrow when Amazon brings my Zippo fluid. I hope the lighter fluid does the trick...

It does look dry as heck in those picks. Take a rag or paper towel etc and soak it in clp or any sort of oil really and run the entire bolt body down with it, not dripping wet but so its got a bit of a lubed sheen to it. You can dry it off later if you are worried about sand etc, for now lets make sure everything is lubed up.

Then take that grease you have or any general automotive grease and put a tiny smear on a qtip and then smear it along this recess and on the back of the bolt lugs where they drag when locking into the action body. A smidge of grease or oil on that roller wheel pin wouldnt hurt either.
You dont want any dry metals sliding against each other even if they are nitrided etc. Its gonna be smoother lubed.

Taking it apart again isnt a bad idea either. Make sure the cocking cam roller spins freely, that there isnt obvious galling going on somewhere. But it is a tight 3 lug, its gonna be heavy on the bolt lift compared to other actions that spread the work load over a wider distance.
If you lay prone behind the rifle or sit behind it at the table, leave your thumb on the chassis and blade your fingers upwards under the bolt handle to lift it, using your planted thumb as leverage to open it, does the rifle tip over on the bipod? If not then it sounds like its working normal and its just a heavy lift action.

 

[D R A K E N B U R G]

I relubed everything. I'm not sure what you mean by the bolt being in the decocked position. I'm pretty certain the bolt is put together properly. It really only goes together one way. Everything feels fine until I dry fire and try to lift the handle. Here are some pics, let me know if these are wrong.

I was just concerned that there might be wrong with the cocoking piece tip and thus result in extra friction when opening the bolt. But from the photo everthing seems fine.

 

[carbonbased]

Sure has a loud “ping!” noise when dry firing…

But I’ve only used R700, AI, CZ 527, Tikka, and Bergara actions. Maybe it’s just the chassis resonating or the vid’s audio pickup or just how that action sounds.

 

[bf2junky]

I was just concerned that there might be wrong with the cocoking piece tip and thus result in extra friction when opening the bolt. But from the photo everthing seems fine.

I appreciate the responses, still working through the issue. I'm in contact with MPA and they want to see the rifle. They are 2 hours from me.

Sure has a loud “ping!” noise when dry firing…

But I’ve only used R700, AI, CZ 527, Tikka, and Bergara actions. Maybe it’s just the chassis resonating or the vid’s audio pickup or just how that action sounds.

Yeah I agree but it has been that loud from day 1.

 

[Mudflap621]

I’d say you’re just not used to the extra weight it’s taking to cock the spring after dry firing. It’s not going to feel as easy as a stripped bolt.

All metal chassis are tingy.

 

[bf2junky]

I’d say you’re just not used to the extra weight it’s taking to cock the spring after dry firing. It’s not going to feel as easy as a stripped bolt.

All metal chassis are tingy.

That's possible, I just don't remember it being that hard to lift. My only other bolt action experience is a Tikka CTR in a KRG Bravo.

Maybe I just need to shoot the thing.

 

[bf2junky]

Thanks for all the replies. I flushed the trigger with lighter fluid yesterday, then some more today and it feels normal again.

Operating the bolt from prone feels normal. Gonna go shoot her Saturday with these new handloads.

 

[carbonbased]

All metal chassis are tingy.

I have heard the same, but my KRG Whiskey 3 is not tingy.

Sounds like the OP was maybe not super experienced on how bolt actions feel when cycling the bolt cocked vs uncocked.

That’s ok. Sometimes we learn stuff by stubbing our toes. Let us know how it turns out.

 

[bf2junky]

I have heard the same, but my KRG Whiskey 3 is not tingy.

Sounds like the OP was maybe not super experienced on how bolt actions feel when cycling the bolt cocked vs uncocked.

That’s ok. Sometimes we learn stuff by stubbing our toes. Let us know how it turns out.

This is my 2nd bolt action. First was a Tikka. I do think the rifle is fine and plan to shoot it tomorrow. I’ll post some results if everything works out.

 

[bf2junky]

Shot the rifle today, everything felt normal. Just need to work on my groups and get a better rear bag! Please ignore the 39.6gr group, total screw up by me.