Thompson Center T/CR22, locking open when shooting.

[Orion8472]

So, I got back from the range. I took my Thompson Center T/CR 22 to sight in a Vortex scope. That part went pretty well. Zeroed at 50 yards and found where [on the reticle] the bullets hits at 100 yards. Not quite as accurate as my target 10/22, of course, but still very good groups. And I was pretty much continually hitting a fist sized rock at the 100 yard mound. So that's good!

However, I was having an issue. Several times, the bolt would lock open when I was still shooting, with bullets still in the magazine. It looks like the bolt hold back lever might be engaging on it's own. My hands weren't anywhere near the lever. This happened pretty much each magazine [was using basic Ruger 10 round and BX-25 magazines], sometime a couple times [or more when using the BX-25].

Not sure if it is a factor, but I was shooting CCI Velocitors.

Any thoughts?

As a side note, also sighted in a new Vortex scope on my target 10/22. Zeroed at 50 yards. Top turret at around 11.5 and hit right on at 100 yards when moving the reticle to 3. Hitting that same rock at the 100 yard mound each time. Very satisfying!

 

[mshootnit]

I would say the Velocitors are a factor.

 

[Orion8472]

That's what I was thinking, but don't recall it happening before. Are you thinking the extra recoil impulse of the Velocitors are overpowering the spring on the bolt hold open lever?

 

[mshootnit]

blowback semi autos can be sensitive to a number of things, ammo and even grip strength if we are talking handguns. Causing timing issues

 

[Orion8472]

I'm just not sure why it didn't do it before, in the past, but now it is. That's what is weird about this. But even so, I can't imagine Velocitors having more recoil impulse...to the point where it would inadvertently cause that lever to actuate itself on its own.

 

[mshootnit]

Velocitors sit squarely between standard 22lr and 22 Mag. So not an insignificant step up.

 

[Orion8472]

So,...they may be causing the issue then. What is the best rifle to shoot them in?

 

[Howland937]

What is the best rifle to shoot them in?

A bolt action.
(Ok, not really)

Are you running those same mags in your 10/22 without issue?

 

[Orion8472]

Yes. The same magazines. Just basic Ruger magazines. But in my other 10/22, it's set up for target and only sees CCI Standard Velocity through it.

I just find it odd that the Velocitors would cause the lever to move that much. Maybe the next time I should watch what it does as I run a mag through.

 

[Odd Job]

Can you verify that this problem does not happen with other ammunition?

 

[Skylerbone]

Can you verify that this problem does not happen with other ammunition?

Great advice. If a problem has a solution, eliminating variables usually gets you there.

 

[Orion8472]

That is actually a great idea, Odd Job. I'll take it back to the range with other ammo next time.

 

[Orion8472]

I took the rifle out to the range today and ran Minimags through it.....and it still did it after only 5 rounds [bolt locking back]. Switched back to Velocitors and again, about 5 rounds and the bolt locked back. But then, I ran another 40 through it.....and didn't get the locking back at all. Very odd. I'll have to go out again, perhaps next weekend,...and will run more Velocitors through it.

 

[Orion8472]

Took it back out to the range today. Shot another 50 rounds of Velocitors and didn't experience the issue at all. So,......not sure what has happening, but may have resolved itself. I did give it a cleaning on Saturday.

 

[mshootnit]

It may be breaking in. I think a "last shot bolt hold open" is a necessary feature for a semi auto 22. There are multiple people who would not be dead or paralyzed if they all came with one.