Watch out for the Keyhole [Archive] - Glock Talk

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DoctaGlockta
04-13-2011, 12:12
Went to the range today to do a couple of things. First to check out to see if my PTR-91 would chow on some German milsurp nato rounds. Read many places that the two did not go together. No problems there - like peanut butter in my chocolate. I'll order some more.

Next on the agenda was shooting some 230 LRN's out of my G30sf. The rounds seemed to be perky and I noticed with many of them that had keyholes in the target at 30 feet. First time for me reloading. Searched the internets and found out it could be several issues. Basically found out that it is a projectile stability issue. Too tight crimp, possibly too much powder or I am starting to get leading in the barrel.

I was using 6.2 grains Unique with a Wolf LPP underneath a 230 grain LRN.

I'll pull a few rounds to see if the bullet looks overcrimped and to check the powder charge.

Appreciate any feedback gentlemen.

Art

Kwesi
04-13-2011, 12:47
Docta: I believe Hornandy has 6.1gr as their max load. I chrono'd 5.7gr with CCI's, 1.240 OAL at 783 Ave FPS.

dt3ft
04-13-2011, 13:03
Get a different barrel

EL_NinO619
04-13-2011, 14:06
To hot I think..

hoffy
04-13-2011, 15:02
Hot load and polygonal rifling-there you go...... I have had plated loads keyhole out of my G-35! Worked up a load for my HK USP C that absolutely drove tacks using tite group. Same load in the 35-couldn't keep all the shots on the target at 25 yards! I am not a bad shot, even won an IDPA style match against 120 guys. So I work up a load for the long Glock using Longshot, which somehow I ended up with 8 pounds of the stuff. Got a pretty good load with the same 165 plated bullets, roughly 1.5-2 inch at 25 yards off bags, and shot them through my USP C and keyholes! At that time I had been loading about 33 years . I loaded a bunch too, and now I have to be careful to grab the right shells for the right gun. I have been using the G-35 when I teach CCW classes so when they are gone, going to have to find something to use the long shot for. I hadn't heard the DAG ammo didn't run in the PTR guns, maybe they are not polygonal rifled. I worked in a gun shop years ago and we got in several cases of that West German stuff and it ran well, we sold a lot of it, but this was in the late '80s . I still have a sleeve of it somewhere, and I saw it in cheaper than dirt and seemed reasonable.

That 40 ammo thing really blew my mind, the HK usually put a mag worth into one jagged hole with maybe a flyer at 25 yards off bags, and then to have the Glock keyhole, and they both have polygonal barrels, crazy man.

I once tried to use .308 bullets out of a shot out Mosin Nagant and boy did they whiz , just like on tv. .311 303 bullets worked for that. I have had great luck with .308 bullets out of my Finnish Mosins though, 1 inch 3 shot groups at 100 yards off a rest, iron sights, but the Finns put really good sights on those guns. I have been threatening to slug the bore for 20 years and have not, it shoots fine. I have seen older bolt guns in 223 keyhole the heavy match sierra 77 grainers, the gun I think had a 1/12 twist IIRC, we checked with a rod.

Colorado4Wheel
04-13-2011, 19:35
Some Glock Barrels just won't shoot lead bullets. It's too early to say about your with just one test. But my 9mm barrel simply will not shoot lead.

WiskyT
04-13-2011, 20:38
Reduce your load.

albyihat
04-13-2011, 21:45
I had some berrys 155gr .40 cal keyhole on me when I first started reloading em. With a light load they would keyhole but with a med. or higher load they shot fine. Don't rule em out till you have used a few different loads.

DoctaGlockta
04-14-2011, 06:13
Reduce your load.

Will do. Should significantly reduce the amount of smoke coming out of the barrel too. The guy in the lane next to me looked over at me and coughed a few times :rofl:

As for my barrel not liking LRN's I have shot many before without problems. That was at about 5.8 grains of Unique. I'm thinking that is where I should be closer to.

Thanks for the responses guys.

Objekt
04-14-2011, 09:49
Normally I'd suggest "back off on the taper crimp," but you have a few different things going on there & it's hard to say which one is causing the keyholing.

I know too-aggressive crimp can make plated bullets go sideways, regardless of velocity (had it happen with both "slow" and "fast" 10mm reloads).

It sounds like you're on the right track.

Milltown
04-14-2011, 12:50
I would drop you unique load back to 5.5 grains with the LRN. I max at 6 grains of unique with 200 grain XTPs.