Bullets keyholing target?

[Wilson]

I'm shooting a 147 gr Lyman bullet over 3.6 grains of Tite Group out of a 9 mm Storm Lake barrel in Glock 23. I often get bullets key holing the target. What causes this?

[docone31]

Too small a diameter.
Slug the barrel, .002 over slug diameter.

[putteral]

Try a slower burning powder. I was having the same problem with Titegroup. Switched to Power Pistol, Unique and AA #5 and it eliminated the keyholing.
:drinks:

[mpmarty]

Thanks guys. My 10mm started making rectangular holes at 25 yards last month and I was going to blame the boolits as too small as cast. They are 170gr Lee tumble lube semi wadcutters. I guess I'll drop the 5.5gr of Red Dot and go with Unique and see what happens.:drinks:

[Wilson]

I did slug the barrel and I'm good there. I'll try the slower powder. I've got a lot of American Select, that I use for 125 grain bullets. Does anyone have an idea of a good starting weight and a max weight?

[putteral]

For the 147 gr I would start at about 3.6 grs of American select and work up from there. I'm not sure that powder is the best for that weight boolit.
:drinks:

[docone31]

I use Blue Dot.
No keyholes.

[mooman76]

Wouldn't a bullet going sideways have more knockdown power?

[bruce drake]

If you hit the target past 25 ft it will make a bigger hole but I wouldn't guarantee a hit...

[MtGun44]

What is your groove diam? You should be shooting .001 or .002 over groove diam.
This is very common with 9mms. Mine shoot best with .357 or even .358 diam.

Bill

[Wilson]

I don't remember the sizes. I'll have to check my notes when I get home on Friday.

[LoveMyJeep]

Too heavy of a crimp can cause the same results.

[Crash_Corrigan]

Gotta go with MTGn44 on this.

My Browning Hi-Power malfunctions on cast of .356 Dia. Dark sooty cases, dirty action, keyholing boolits. Up the dia to .358 and LEE FCD lightly and I get extreme accuracy, clean gun and no malfunctions.

My Tangliofolo Match Elite handles .356 just fine and will not chamber a .358 boolit even if a crank down the crimp with the FCD.

I did not bother to slug either gun as my results float my boat.

[Down South]

Too heavy of a crimp can cause the same results.
This is possible. Can you make a dummy round then pull the boolit and mic it? See if the crimp is sizing the boolit.
Are you using an FCD? They can resize your boolits too.

[Jim_Fleming]

MooMan, you & Bruce Drake are a pair... LMBO! A pair of blinkin' fruitcakes! I laughed my butt off at both of your one liners...

Good Job Gents!



Wouldn't a bullet going sideways have more knockdown power?

[epj]

Had the same problem with some commercial cast 9mm and Tightgroup. Switched to 231 and had no more problems. Never did mike the boolits. They were advertised to be .356, but I miked some of a similar type commercial slugs from the same maker and found them a bit small. I have found many, but certainly not all commercial cast boolits to be undersize.

[ChuckS1]

I think the diameter is the issue. Had that happen once when I fired .44 Specials in my S&W Model 25 .45 ACP revolver.

[Matt_G]

I've got a lot of American Select, that I use for 125 grain bullets. Does anyone have an idea of a good starting weight and a max weight?

I can't find any load data in my books for the 9X19 using a 125 gr. cast bullet and American Select powder.
However, my Sierra manual does list a 125 gr. JACKETED load with American Select.
Starting load is 3.5 grs. (900 fps)
Max load is 5.0 grs. (1100 fps)

FWIW