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Discussion Starter #1
I would like some help deciphering this situation that happened tonight.

Loading Once-fired 45ACP brass with 4.0gr Titegroup, with a lead 200 grain semi-wadcutter. OAL 1.225

Chronograph from my autoloader (Tanfoglio Witness) gave 450 fps instead of the expected 800 fps.

230 grain hardball used to check chrono out of same gun gave 924 fps (intentionally hot load).

Next lead bullet gave 454 fps.

Same lead bullet and load out of a Glock 45 gave 824fps.

Gun has about 800 rounds through it. All jacketed bullets give good performance.

Any ideas?
 

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Perhaps a goof on the powder in that batch? unintentional light load?
I don't load my own(yet), so I'm just shooting in the dark. (pardon the pun)

I'd suggest double checking your recipe and loading a new batch. Maybe a diff powder will work.

It's late, and I'm bored. Please don't beat up the noob for giving an experienced hand loader suggestions.:ahhhhh:
 

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The Hornady manual starts out with 4.5g of titegroup at 800fps with a 200g lead bullet using Win primers. How long is your barrel? Horady used a 5 inch barrel.
 

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Discussion Starter #5
Maybe I need to clarify....

I actually don't have a problem with the powder/primer/bullet combination. This is a light load that I am putting together... The load is 4.4 Titegroup, Winchester primer, and swaged lead 200 grain Semi-wadcutter with single lube groove, OAL 1.220, with taper crimp.

I rechecked my powder drop, disassembled one of the cartridges from the 10 round assembly run, and found the proper specs.

I really don't have a problem with the load, as it gave me over 800fps from the Glock.

My real problem is that MY pistol will give only 450fps with this load, even though the 230gr FMJ I shot between tries with the lead bullets gave me 924fps.

My barrel length is 3.6" and I expect 30-40fps lower than the 5" barrel in most cases (this has been fairly consistent through testing a bunch of loads).

(Sorry about any confusion, the load is 4.4 Titegroup... I wrote the original post at 2am and didn't have my notes handy)

Thanks,
Mike
 

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I would expect more than 450 fps. Maybe closer 700fps to 750fps. Maybe you are having a problem with muzzle blast with your chronograph. I have had some weird things happen with sub-sonic loads. I have some 38 spl loads right now that should clocking about 800 fps chronographing at 1450. Had to play around with the distance for muzzle to chronograph.
 

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Discussion Starter #7
I don't suspect muzzle blast or other chrono funnies because...

1. It was consistent for the lead bullets. All were in the same fps range
2. Chrono reading from the FMJ is right where it chronoed before
3. First screen is 10 feet from muzzle
4. One of the lead wadcutters BOUNCED OFF of the plywood without being deformed. Except for the rifling marks, you couldn't tell it from a new bullet!:gah:

Thanks for the ideas, it is helping narrow it down.
M
 

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Check the diameter of the bullets. Undersize bullets will allow gas to escape around them, decreasing velocity.

Too light a crimp can also result in low pressure / low velocity.
 

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I have no idea then. You could slug your barrel and make sure you have a good barrel bullet match. I would be concerned about a barrel obstruction occurring if you are bouncing off plywood.
 

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Check the diameter of the lead bullets compared to the FMJ bullets and then measure the bore on both pistols. I believe the above numbers will answer your question. Also do you know what hardness the lead bullets are?

NCH
 

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You aint supposed to shoot lead bullets out of a stock Glock.
 

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Discussion Starter #12
The next step is to slug the barrel. Already have that set up.

NCHornet -
The FMJ was .451, the lead was .452, and the bore at the muzzle was around .450 (I didn't mic it, someone else did, so I don't remember the number, but was it was determined to be compatible). The bullets are by Houston Bullet Co, and had no markings other than the caliber and weight on the box, so I have no idea the hardness.

My new theory is that the chamber end of the bore is not as tight as the muzzle end allowing initial blow by. The slugging should tell me the story.

A friend was wondering if it was possible that the 3.6" barrel in the compact was optimized for jacketed bullets and did not handle lead by design. Does any manufacturer do this?

RamRod-
I understand that. The owner of the Glock was informed of this and we only fired one. Just to verify the chrono setup wasn't wrong on lead bullets. I thank you for your concern.

Thanks for the dialog, it helps keep me sane in the lack of evidence....

M
 

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I would probably load up five rounds with a different powder just to see.
 

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Check the diameter of the bullets. Undersize bullets will allow gas to escape around them, decreasing velocity.

Yup. My thoughts as well. It would explain the performance in the glock too- glock's have polygon rifling which behaves differently then more traditional ones.

Yes, one must be careful firing lead out of Glock barrels...
 

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Yup. My thoughts as well. It would explain the performance in the glock too- glock's have polygon rifling which behaves differently then more traditional ones.

Yes, one must be careful firing lead out of Glock barrels...
Not to hijack the thread but can someone explain to me why Glock’s polygon rifling causes a problem. I would seem to me that being smoother than cut rifling it would cause fewer problems with leading and pressure buildup.
 

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Mprasek, you said 'light loads'.

Powder does not always burn uniformly if the pressure level is under a certain threshold. Powder burns best in the upper end of the allowable pressure range.

Your light load may be in that threshold level and therefore doesn't burn as it should for best results - just like acetylene doesn't burn very well without some pure oxygen in the mix.

Try bumping the powder charge up a notch (size of the notch is up to you, don't jump to maximum) and see if the velocity spread doesn't get better.

Other questions: NO, no manufacturer makes a barrel by length that favors jacketed over lead. A barrel with shallow grooves will sometimes shoot more accurately with either jackets or very hard lead, but the velocity isn't affected.

And, for the nth time, Glock does not specifically proscribe lead bullets; they recommend against all reloaded ammunition. It's a lawyer thing. Nor do polygonal bores - which Glocks are not, despite their advertising - have a problem with lead bullets vice jacketed bullets. (H&K have polygonal bores, look at the difference some time.)
 

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And, for the nth time, Glock does not specifically proscribe lead bullets; they recommend against all reloaded ammunition. It's a lawyer thing. Nor do polygonal bores - which Glocks are not, despite their advertising - have a problem with lead bullets vice jacketed bullets. (H&K have polygonal bores, look at the difference some time.)
Regardless GLOCKS have a problem with lead bullets. Excessive bore leading occures when shooting lead bullets, which can cause a presure increase which can/does cause a failure ( Ka- Boom). Also accuracy goes south after a few rounds.

I have been shooting Glocks since 1985 and have not experienced a faliure, but have expericensed servere leading and very poor accuracy when shooting lead bullets.

Replacing your stock Glock barrel ( which i have done)with an aftermarket barrel will allow you shoot lead bullets without any problems that would not occur with any other handgun with a normal rifled barrel.

The shooters on this forum

Brian Enos's Forums... Maku mozo! (Powered by Invision Power Board)

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Shoot IDPA, USPSA, IPCS, Bianchi Cup, Steel Challenge, etc and a lot of them shoot more then 50,000 rd per year in matches and pratice.

There are several warning's on this forum about shooting lead bullets in a Glock with a stock Glock barrel.

IMHO based upon my experience and research I firmly believe that this in not a myth

http://www.thegunzone.com/glock/kb-notes.html
 

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I will have to go along with Archie here and bump the powder up a little. Hornady list the starting load with a 200g lead bullet at 4.5g (800fps), 4.9g (850fps), 5.2g (900fps), 5.6g (950 fps). They used a 5 inch barrel. Use at your own risk and work up slowly, blah, blah, blah.
 
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