Mossberg MVP Light Primer Strikes

[oDbCo]

I bought a Mossberg MVP in 5.56 at a gun show on Saturday. I'm having some light primer strikes with 5.56 American Eagle XM193, but .223 sems to have no problem. I called Mossberg and they said to send it back and it would take "several weeks" for them to touch it. Should I try to have a local gunsmith look at it or just send it back to Mossberg?

 

[TacticalFun]

Is it new or used? Does the firing pin move freely? The trigger is adjustable. Check to make sure hammer i engaging completely

 

[M67]

Take apart your bolt and check the firing pin, might be excessive grease in the spring

 

[singlesix]

Do you know you local gunsmith? Does he do good work (based on actual customer's who had work done). I seen really messed up firearms worked on by "local gunsmiths".

 

[oDbCo]

It is lightly used. I disassembled everything, cleaned and oiled. Still having the same problem.

 

[oDbCo]

Do you know you local gunsmith? Does he do good work (based on actual customer's who had work done). I seen really messed up firearms worked on by "local gunsmiths".

No I do not know any gunsmith. I just don't want to wait several weeks when I can get it done without shipping it to Mossberg.

 

[oDbCo]

Is it new or used? Does the firing pin move freely? The trigger is adjustable. Check to make sure hammer i engaging completely

I tried adjusting the trigger and no luck on heaviest and lightest setting.

 

[M67]

It is lightly used. I disassembled everything, cleaned and oiled. Still having the same problem.

Is the firing pin hole on the bolt face clear? Firing pin not deformed?

Does the rifle chamber 5.56 ammo easily or does it require a little extra effort to get the bolt handle down?

 

[oDbCo]

Is the firing pin hole on the bolt face clear? Firing pin not deformed?

Does the rifle chamber 5.56 ammo easily or does it require a little extra effort to get the bolt handle down?

Yes, the bolt face is clear and the firing pin looks good. Both 5.56 and .223 chamber smooth.

 

[M67]

Yes, the bolt face is clear and the firing pin looks good. Both 5.56 and .223 chamber smooth.

Either Federal had a batch of extra hard primers, or your firing pin spring is weak. Do they fire on the second chambering?

When you pull the trigger is there a clean break or does it feel mushy?

 

[oDbCo]

Either Federal had a batch of extra hard primers, or your firing pin spring is weak. Do they fire on the second chambering?

When you pull the trigger is there a clean break or does it feel mushy?

I was able to succesfully fire the unfired rounds through an M&P15, so I don't think it's the ammo. Trigger breaks clean.

 

[oDbCo]

Either Federal had a batch of extra hard primers, or your firing pin spring is weak. Do they fire on the second chambering?

When you pull the trigger is there a clean break or does it feel mushy?

The rounds that the MVP did not fire were able to fire out of an M&P15 and the trigger on the MVP is always crisp.

 

[M67]

The rounds that the MVP did not fire were able to fire out of an M&P15 and the trigger on the MVP is always crisp.

Firing pin and the sear have good contact then, sometimes if the firing pin slips off the sear it slows momentum just enough

I'm sticking with the firing pin spring being a tad too weak. Especially if you've taken it apart and there wasn't any excess grease or rust in there

 

[oDbCo]

Firing pin and the sear have good contact then, sometimes if the firing pin slips off the sear it slows momentum just enough

I'm sticking with the firing pin spring being a tad too weak. Especially if you've taken it apart and there wasn't any excess grease or rust in there

Should I send this to Mossberg or is this something that a gunsmith closer to where I live can fix?

 

[TacticalFun]

You can order a spring. Easy change.

 

[DanVoils]

You can order a spring. Easy change.

If you get the right person you can get them to send it to you for free. I've called before needing a spring or screw that "disappeared" off the work bench and they sent it to me at no charge. Worse case you have to pay.
I tend to agree with the spring being light. I have an MVP. We could meet at a range and swap bolts. This would quickly let you know where the problem lies. Put my bolt in your gun and then your bolt in my gun. I'm on the westside. We could meet at Parabellum in Avon one evening. Shouldn't take too long to figure it out.
Dan

 

[BoilerMakerME]

I won a new MVP about 2 year ago, same issue with American Eagle XM193. I was always told that the hardened military primers might not always fire in bolt guns. I've seen the same thing with XM80 7.62 x 51 in a savage bolt gun (twice in about 30rds). In the MVP I've probably had half a dozen weak strikes (out of say 100rds) from memory (this was over 2 summers) i think they went off the 2nd or 3rd time, but if not use them in an AR. If you can't live with it i'd guess send it back, i'd hate for you to send it back and wait, and then all you do is get the same results. I don't know if someone makes a stronger aftermarket firing pin spring.

 

[oDbCo]

Could I add a nylon washer like this to the firing pin assembly to further compress the firing pin spring thus making it stronger?

100X White Plastic Nylon Non-Threaded Standoff Spacer Washer M3 M4 M5 M6 8 Screw | eBay

 

[DanVoils]

Could I add a nylon washer like this to the firing pin assembly to further compress the firing pin spring thus making it stronger?

100X White Plastic Nylon Non-Threaded Standoff Spacer Washer M3 M4 M5 M6 8 Screw | eBay

Makes sense it would. Obviously diameters would have to match.
Dan

 

[Leo]

Could I add a nylon washer like this to the firing pin assembly to further compress the firing pin spring thus making it stronger?

100X White Plastic Nylon Non-Threaded Standoff Spacer Washer M3 M4 M5 M6 8 Screw | eBay

Before shimming a spring, you need to know the minimum collapsed length of the spring and the amount the mechanism needs to collapse it. There is not a lot of extra room on some firing pin springs. Coil bind is not a good thing either. I have, as suggested, changed springs that had grown weak.

Be sure to post what solution you find that works, I know quite a few people have the MVP rifles.