Bolt on Mark III Hunter Failing to Lock

[ncspeedsix]

Hi all,
The bolt on my Hunter does not lock back after each mag is emptied. I take down and clean my mark pistols each time I shoot them. My mark II has never had this problem but my Hunter has been doing it consistently since the 500 round mark. Other than this, the pistol has been great. No FTFs or FTEs of any kind. Any ideas or suggestions?
Thanks!
NC Speed Six

 

[ranger1]

How do chamber a new round after reloading?

Are you using the bolt release button or do you use the slingshot method?

 

[SR-SP101]

How do you drop the bolt? It is recommended to "slingshot" versus hitting the bolt stop. Over time the bolt stop contact edge will round off and fail to hold the bolt back. I would try replacing the bolt stop. They are inexpensive and fairly easy to change out.

 

[ncspeedsix]

Thank you for the advice. I have been using the sling shot method.

 

[blume357]

I use the bolt stop lever myself, most of the time.... and mine still locks back... but I think you folks are right, that is what I would try... replace that part.

 

[Anonymous]

The bolt stop tends to pick up a lot of crud that can bind it. I would check that, all the way to the plunger and spring for it that are up near the trigger.

 

[Rick Courtright]

Hi,

I'd try Bearcatter's suggestion first: crud builds up a whole lot faster than metal wears down!

Rick C

 

[Deadeye Tom]

Does this happen with more than one magazine? You might want to look at the follower for damage or other problems. If it only happens with one mag, this might be the issue.

 

[Mobuck]

Too much cleaning. Just kidding,but if you're not shooting 1000 rounds per outing, you likely don't need to clean every time.
It may be the ammo you're using. I have a newish MK3 that won't consistently lock open with Federal ammo but works fine with some hotter HV Remington.

 

[ppknut]

OK.......I been having the same problem with my M III Comp.

I inspected the bolt stop and found the leading edge to be somewhat rounded off. Suspecting this was the problem, I replaced the bolt stop with a brand new one.

Still having the problem with no bolt lock on last round.

So... I have inspected the magazines. I have six. All appear identical. Feed lips are visually identical. A couple of them will lock back. the other 4 will not (unfortunately, I haven't numbered them yet to see if there's a certain mag or mags that are consistently not functioning properly).

There is some wear on the rear of the plastic followers. That will be my next purchase. I will replace them.

If that doesn't fix it, is it possible there could be something amiss with the bolt face...the part that comes into contact with the bolt stop? Inspection reveals what appears to be a little rounding of that 'corner' of the bolt face.

I'm also thinking about the recoil spring being part of the issue. Can this spring (weak or strong) cause the bolt not to lock back?

 

[Anonymous]

definitely try another magazine, it might just be an issue with the one magazine.
Eric

 

[ppknut]

As I said, I've already got 6 magazines. I'd rather not buy a new mag only to find out it's the followers that may be worn out.....or the bolt itself which may be "eroded."

 

[Anonymous]

Hi,
I did not see you had 6 magazine you tried, well it is not that adnd most likely something with the bolt but that still sounds odd to me , if you have pictures of the bolt and inside of the gun it might not be a bad idea to post them to see if I can figure something out, hard to tell you what it could be for sure without seeing it in person or pictures like if I was there in person.
Eric

 

[ppknut]

I'll try to get some pix of the bolt face in the next day or two. In the meantime, I'll probably order a few followers (gotta be cheap) and give them a try.

 

[ppknut]

Here is a picture of the bolt face. Notice the slight rounding of the edge of the face which comes in contact with the bolt stop. I'm thinking this rounded edge contributes or causes the bolt not to catch on the bolt stop.

I'm also still wondering if the recoil spring could also be a possible cause.

ETA: If this is the cause, and I need to replace the bolt, would that be a "drop in" part?

 

[rooger]

ppknut , the face of your bolt looks like my own MKIII's and I do not think the rounding is the cause of your problem. I had to put in a new bolt stop to cure my own failure to lock back. I had worn it out prematurely by not using the slingshot method. Now I know better. Even though you are releasing the bolt correctly, I think you should carefully examine the bolt stop. From experience, I know old mags can also cause the problem you're having. Too loose of a grip, a dirty gun and crappy ammo are also suspects. Good luck...I know how frustrating this problem can be.

 

[ppknut]

As I indicated, I just replaced the bolt stop, so it's brand new. And the failure to lock back continues on like 4 out of 6 magazines.

I guess I'll try the mag followers next, but still interested to know if the recoil spring could also be a possibility.

 

[Collector1337]

I don't think it's the recoil spring, if it was weak, it would just lock back easier, not harder.

I'm assuming your gun is clean and well oiled right?

Have you tried ammo over 1300 FPS?

 

[ppknut]

You know, I hadn't thought of the ammo. Just using standard Win or Rem Wally world bulk packs.

I'm one of those crazy people that spend more time cleaning my stuff than using it. So, it's pretty spotless most of the time.

I don't have a chrono anymore (son took his with him when he went off to school). So I have no idea what the velocities would be of the inexpensive .22's.

I will say, that this is the only type of ammo I've used in this gun. And it used to work fine. I will do some experimenting with ammo however.

Thanks for the ideas.

 

[rooger]

And the failure to lock back continues on like 4 out of 6 magazines.

Is it always the same four mags? I have six. I numbered them so I could determine which ones were causing problems. Sure enough, my old ones would have failures to lock back. With my two newest mags, I don't have failures to lock back. I carefully examined the old ones and the new ones and I cannot see any differences...but they are definitely different in some subtle aspect.

 

[ppknut]

I just finally numbered them tonight. All my other mags for my other arms have been numbered for years. I just never got around to it on the Ruger mags.

I'm going out this weekend with the numbered mags and some different ammo. We'll see...........

 

[ppknut]

Update.

Took the M III out today with numbered mags and different ammo.

Worked flawlessly! Every mag, every time. All locked back.

Turns out the ammo seems to have been the problem. I was shooting cheapo bulk ammo with a stated velocity of 1,260 fps. The only different stuff I had was rated at 1,280 fps. So the higher velocity seems to have made a big difference.

I now wonder, if I really needed to have replaced the bolt stop (although the old one did look somewhat worn). That was a good excercise anyway, as I finally learned how to do a detail strip on this piece.

Thanks to all of you with your ideas! Much appreciated.

-ppknut

 

[rooger]

Good going, pp! Thanks for posting your solution so others may benefit. Care to identify the problem-causing ammo and the problem-free ammo you used?

 

[ppknut]

The ammo that wouldn't cycle properly and lock the bolt back was Federal 550 round Value Pack. Its stated muzzle velocity was 1,260 fps. Typical Walmart .22LR.

The ammo that worked was Winchester bulk pack of 555 rounds. Its velocity was rated at 1,280 fps. I probably also got that at Walmart, but can't be sure.

I find it interesting that those 20 extra fps would have that much effect, but clearly it does.

I'll have to use up the Federal ammo using my Marlin 39A and Ruger bearcat. You can be damn sure the next time I buy any 22's they'll be rated at lease 1,280 fps!

ETA
BTW, thanks to Collector 1337 for the ammo suggestion.

 

[Collector1337]

I thought it could be ammo, but it still seems weird.

I've shot my MK3 Competition 2 times this week. Once was with the Federal blue box 525 round count and once was with the Winchester red box 555 round count.

Both worked just fine for me. I personally think the blue box Federal is better than the red box Winchester. Most of the red box stuff the bullet will turn in the shell, whereas the blue box stuff they are mostly tight. Maybe that doesn't really mean anything, but the Federal bulk has always seemed better than the Winchester bulk. The Winchester gives a really funny burned power smell, that's kind of unpleasant. But the Federal smells like normal good smelling gun powder when shooting. (I notice easy since I'm shooting indoors.)

Maybe you just got a bad batch?

Either way, glad to hear is seems to be working fine. Look at replacing the bolt stop as a learning experience. And has one less part you have to worry about down the road.

 

[firebirdude]

Practically all I shoot out of my MKIII hunter is the Wally World Federal bulk pack. Probably had 5,000+ rounds of it through it without any of the described issues. Rarely a malfunction either.

 

[Mobuck]

Like I said in my previous post(response #8), the ammo could be (was) the problem.

 

[ppknut]

Like I said in my previous post(response #8), the ammo could be (was) the problem.

At least, for me, this is correct. Whether a bad batch, or lack of velocity, ammo was this issue.

 

[DVRich]

I use the bolt stop lever myself, most of the time.... and mine still locks back... but I think you folks are right, that is what I would try... replace that part.

If you use the bolt stop lever to release the bolt, you will ruin the lever. Been there done that and I got an interesting note from Ruger when the pistol came back. They said this repair was on them but the next time they'll be a charge.
Ruger is excellent with customer service even if the user is at fault.

 

[ncspeedsix]

In my case, I finally figured it out and it was the Altamount grips that I had recently installed. Due to where I was putting my top thumb with a thumbs-forward grip, I was inadvertently riding my bolt release. I changed my grip slightly and the problem went away. Simple enough! Thanks for everyone's help.