cpa5oh

Thank you!

Thanks for the replies. Ill call grams or order grams spring/follower kits. How many coil springs do I want? I've got a few mags with 11, a few with 13...

I need new springs for my 140mm magazines. I use Grams followers. Grams replacement springs are out of stock at both places I normally would buy stuff from (shooters connection and CPWSA). There are other options available: arredondo "+10%", wolff, taran tactical, MBX, and ISMI. Anyone have any recommendation on what I should get? Not sure which will work with Grams followers. Other option is to just buy Grams spring/follower kits - it's double the cost but maybe it's the way to go?

Did some searching for "victorious grip tape"... What I found was "vicious grip tape": had to sit through a skateboarding video in the process. It's available on Amazon and other websites but the problem is that black is out of stock (it's even out of stock on the manufacturer's website). The video I sat through mentioned "Madrid Thumb Cutter" grip tape as equivalent to Vicious and that was available on Ebay so I bought some. Doesn't seem very economical (either brand) compared to other grip tape: looks like you get 4 10x11" squares for about $22 as compared to regular grip tape at around $5-$7 for a sheet big enough to cover a skateboard (which I think is about 10x33"). Price doesn't much matter to me because I only shoot on weekends so as long as it's semi-durable I shouldn't be burning through the stuff. More interestingly, the video I watched talked about cleaning grip tape: a product called "Grip Gum" was recommended as was whatever it is that is used to clean belt sanding belts. Amazon popped up this and I ordered it: https://www.amazon.com/POWERTEC-71002-Abrasive-Cleaning-Stick/dp/B00AJW0CY8/ref=sr_1_3?ie=UTF8&qid=1498648359&sr=8-3&keywords=grip+gum

I don't think set-back could be an issue - with the U die and .401 bullets there's a lot of tension up at that bullet. But definitely the gun being just slightly out of battery because a round didn't completely chamber is a possibility. The chamber was dirty enough where rounds weren't passing the "plunk" test until I cleaned it. I've gotten rid of the extended firing pin and cleaned the barrel very good and plan to clean it after every couple of hundred rounds - if that doesn't do the trick I won't be sure what to try next, but I think it's going to work.

Great idea with the sharpie - I'll do this. Definitely have enough neck tension - I'm running coated bullets into dies sized with a Lee "U" die and the case has a noticeable bulge to it up at the top where the bullet goes.

That's s great point and probably blows up my firing pin getting stuck theory. Beyond your comment, now that I think about it, I'd have been getting doubles if the pin was stuck hanging out through the breechface. i guess I'm left with a dirty chamber not allowing bullets to fully seat and somehow the gun being capable of setting such a round off.

I do chamber check every round using the Ben stoeger/shock bottle chamber checker. Rounds that pass that checker all plop right into the barrel chamber when it's clean. However, that chamber was dirty enough to where rounds weren't plopping in free and clear. i made several changes and ran 100 trouble free rounds through it: went back to the stock firing pin, upped the mainspring to 19 (so I wouldn't get light strikes), tuned the extractor, and cleaned the barrel real well. Fingers crossed that I won't have more blowouts. thank you for all of the replies they were very helpful. I'll report back so that in the future if anyone looks this topic up an answer will be in the thread.

I do load my ammo short (1.130") because I mainly shoot a CZ Tactical Sport in Limited, but that's always been the case and this case blowout shit is a new phenomenon.

I don't think anything external is different between an AET and non-AET barrel (could be way wrong, though). I thought it was just a little difference to the chamber and more difference to the rifling (gain-twist). Gonna try the factory (non-extended) firing pin, extractor adjustment, and a new firing pin spring and see if that doesn't end the case blowouts.

Barrel is AET. I am reloading my own ammunition. 180 grain coated bullet with 4.2 grains of Ramshot Competition. Same reloading setup/load as I have used without problems for the last three years loading .40 (and currently shoot from other guns). Brass is mixed range pickup stuff. If I have to start sorting brass to shoot this gun it'll be on gunbroker at a fire sale price :-)

I've got an STI Apeiro and, in the last week, I've had 4 case backs blowout. They definitely aren't over/double-charged rounds - the explosion isn't violent at all and the same batches of ammo have been run through other guns (including another 2011) and I've had no issues. I know that I had zero extractor tension (had failure to extract incidences the last few times I shot it, checked it, and the extractor wasn't holding cases to the breechface at all - could slide a case right through the extractor and the extractor almost wouldn't touch the case). Not sure if that could be a cause of case blowouts - I'd imagine that improper tension wouldn't cause blow outs, but maybe a complete lack of any tension at all could? Only other thing I can think is that I remember the extended firing pin being a tight fit in the breechface - might be possible that occasionally it's getting hung up and catching the back of the primer just before the slide closes... Anyone have any experience with 2011 case blowouts and any thoughts on what the causes could be? Thanks!

Just got an email reply from them: you have to order 10 at a time. I imagine that means they don't want to be bothered by non-builders (or local gunsmiths).

I'm sure that it does not.