Accuracy problem with Kead bullets.

[Jimlakeside]

I am new to reloading, and to this forum so any advice will be helpful. Here is the situation:

Stock Glock 34 9MM
Kead 9mmRN 125 grain bullet
Vihtavuori 340 powder 4.7 grains
Winchester brass (white box) mostly
Wolf primers
Chronographed 5 rounds from 1071 to 1084
Bullet diameter measures .355 by my caliper (remember I am new and never measured a bullet before)

The bullets are all over the place and at least 2 out of 5 keyhole. From reading this forum, I suspect the bullet diameter is too small.

My question is this - is there anything I can change to get more accuracy? Also will buying an aftermarket (Lone Wolf) barrel make any difference?

I will work up another load this week and shoot them through my wife's Kimber to see if they are more accurate then.

Thanks for you input in advance.

Jim

 

[Unclenick]

Kead advertises that bullet as being .3565", which, if correct, would be about right. You generally want a lead bullet 0.001" to 0.002" over bore diameter. My guns prefer the latter. Check zero on your caliper. Wipe the jaws off and bring them together by pinching the jaws closed between your thumb and index finger. When measuring, try that pinching technique, too. You want the jaws to kiss the bullet, but don't apply clamping force with them. That will flex the jaws and give you a low reading. Try measuring a jacketed 9 mm or .357 bullet with it to get a rough calibration. They should be about on number (.355" or .357").

Lead bullets keyholing suggests you have some blowby. Check your barrel for leading and get it thoroughly cleaned out if you have it? Wipe Out's new No-lead product works very well for this. A constriction of lead deposits will cause lead to shoot very badly. Assuming your magazines still hold the longer rounds OK, seat the bullets out far enough that the casehead is just flush with the back of the barrel when you drop a loose round into the chamber. Use the barrel as a gage, that way. A round that drops way into the chamber will be headspacing on the extractor hook, and a lead bullet is too soft to straighten itself out going into a throat as a jacketed bullet will.

Get a little bit faster powder. Higher pressure earlier in the bullet travel will better obturate the bore to prevent blowby. N340 is a good 9 mm powder for jacketed bullets, but with lead I would try something more like 3.7 grains of N320.

 

[Jim Watson]

In addition to Unclenick's good points, it is just plain difficult to get good results from a lightweight cast 9mm bullet. I suspect the short bearing surface of the bullet and the fast rifling twist of most 9mms. The "polygonal" bore of a Glock does not help.

I know a successful lead bullet Glock shooter here. He uses heavy bullets, fast powder, and settles for low velocity. A 158 at 800 to make IDPA SSP power factor. Sounds a lot like a .38 Special, doesn't it? And those have been working since 1899.

 

[wingman]

I know a successful lead bullet Glock shooter here. He uses heavy bullets, fast powder, and settles for low velocity. A 158 at 800 to make IDPA SSP power factor. Sounds a lot like a .38 Special, doesn't it? And those have been working since 1899.

Good advice, check the barrel for lead and slow up velocity think you will
have better luck. I'm not a big fan of lead loads any more have used with
excellent results in 45acp but the cleaning and dealing with lead just soured
me on there use.