Who's the #@%&* who told me I could shoot .40s&w out of my 10mm bbl?
 

because it worked just fine in the G29, thanks for the tip :wavey:

The chamber was a little dirty but after shooting about 70 .40 cal rounds, I loaded up 7 rounds of full power 135gr Underwood 10mm and they still chambered and fired ok. Big difference in sound after shooting all those 40's. I think I woke everyone up on the firing line.

Oh the noes! Now little puppies everywhere are going to die and little children will weep, you will go sterile and people will hate you.

:-)

What would happen in the full size G20 barrel?

I don't have a Glock 20 but other folks have posted in this thread saying they have no problem with it.

http://glocktalk.com/forums/showthread.php?t=1442850


This will solve my problem of plinking ammo for the 10mm. Bought some .40 Federal 180gr at wal mart for $25 per box of 100. That's approaching 9mm prices. And I have a 23lb recoil spring but still had no problems other than it didn't seem to throw the brass very far, sort of fell on my shoe is more like it.

Nothing. Not a single thing!

(Unless you load a mag, insert it, cycle the slide, and pull the trigger. In which case, it will go bang, and a bullet will go where you're pointing your pistol. Other than that, quite uneventful....)

OMG that is so cool, didn't know you could shoot. 40 out of a G20 stock barrel. Sort of solves the range plinking cost dilema of 10mm ammo.

You have gone and done it now! Shooting Short and Weak in a 10mm Barrel :wow: ...SHAME on you! What where you thinking? :dunno:

Have at it. Not me! Good to know in a pinch, though.

This. 10mm headspaces on the case mouth, running a 40S&W case in a 10mm chamber means that the extractor is the only thing holding it in.

Theres a sucker born everyday.... .40 Smith.. LMAO!

I found out something about this recently. I had a bunch of 40 brass that I wanted to decap with live primers (long story). I had my G20 onhand and loaded them from magazines one at a time.

Observations:

Because the cases "head space" on the extractor, many had very very light primer strikes. Some did not fire the first try. A heavier loaded round would likely be less susceptible.

Secondly, extractor abuse. On about 1 out of 5, the case would slip out of the extractor upon primer strike, and was forward inside the chamber. What this tells me is that a live round could slip past the extractor during the engagement of the striker. Upon ignition, the case would slam backward against the extractor and then the breach. It would be like single feeding a 10mm round into the chamber and then letting the slide slam home. You wouldn't know this just by shooting live rounds. Doable in a pinch, but seems a bit unecessarily abusive.

Not true. The case mouth is only a limiting factor. Your 10's still space off the extractor, unless the case is long enough to hit both (about 1.002"). As the slide/breach picks up a round from the mag, it slides up the breach, and under the extractor. The case rim is (should) never be forward of the extractor. If it is, it won't fire.

If your going to do this u really need to make sure your extractor holds them tight. I can tell u that.mine did not. I ended up welding mine up and re cutting it to hold it like I wanted.

I think you will find it different if you use loaded ammo. I have had none of those issues in 700 or more rds.

I shoot them all day in my G20. I don't think it matters, relatively. Just check your extractor and clean your chamber well...esp. b4 going to 10mm rnds. Also, I haven't heard anyone doing this in an auto other than a G20/G29, though. I can't speak for other platforms, personally.

"Never Cross the Beams!" ;-)

OP, BTW, that's a great way to start a thread if you want fast attn! :wow:

Exactly... 100%. Doable in a pinch, otherwise, do it right. That's my take on it.

Agreed with NickE .......Reload your own 10mm rds for "plinking" (if anything from a 10mm could be called plinking) ....LOL

Huuummmm....

I believe the OP doesn't reload...?

My point is that you wouldn't necessarily know if that was happening. It could very well be, but I hadn't considered that until seeing how the stricker popped the case out of the extractor in a significant number of instances. You could be right though. It is hard to know for sure.

I would wonder if I had come across the same results you had. Not arguing them, just wondering why the discrepancy exists. I can't get a round to skip past the extractor by hand, and haven't had light strikes; I can see a brass mark on the front of the extractor, but it doesn't look like the case is sliding back over it, more like it is bumping against it. I think I have over 200rds of .40 loaded long w/out any malfs, and the few I had before that (1/50) were due to a poor crimp.

I have only tried a couple of variations on the theme, and in an AM barrel, but haven't had any issues with what I have used. Just wondering why the primed cases worked differently,(I don't think I am having the problems you saw). On BE, one guy had all kinds of issues with light strikes and accuracy in a non-Glock, who knows why it worked in one gun but not another?

I shoot 9mm outta my 10mm and save alot more money than mosta u combined, so ha...

I shoot 9x25Dillon from my 10mm, but I change barrels!

Careful what you suggest. Someone's gonna try it. (we're not ALL rocket scientists, ya know....)

I've had a few 9's go through my G22's. All were non-events. Just fired, FTE'd, cleared weapon, checked bore, and life goes on. They were actually fairly accurate. I DO NOT recommend anyone try this (intentionally, anyway).