Tanfoglio Witness does not shoot lead well

[mprasek]

I have a Tanfoglio Witness Polymer Compact in .45ACP.

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 gun gave 450 fps instead of the expected 800 fps.

230 grain FMJ used to check chronograph 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?

Thanks for the help.

[GunslingerDK]

Hmmm... never heard this before. Now pardon me for asking, but I assume we are not talking about squibs?

If you do not have much experience in shooting lead I can give you a few basics. Make sure to slug your bore so you know its exact size, and size .001 over groove (PM me if you do not know how to slug a gun). For the velocity range you are looking for wheel weights or an alloy of equal hardness of about BHN12 will suffice. Is this commercial cast or your own creation??

Maybe the primers somehow failed to ignite all the powder?

[liontribe]

you may already know but it is a no-no to run lead in glocks with the factory barrel. be very careful. lots of glock have gone kaboom from running lead in polygonal rifled factory barrels. best.

liontribe

[mprasek]

The bullets were .452 lead bullets from Houston Bullet Co. No hardness available.

The barrel will be slugged in the next few days to see what it is.

We are not talking squibs, the bullets hit the target (and one bounced off). The firing from the glock confirmed the loads were functioning. The low velocity happened with 6 shots with the lead bullets using 2 different powders.

I think that the compatibility of the lead with my barrel is the most likely reason.

Liontribe-

I understand about the Glock and lead, and informed the gun owner about the need to clean and risks before we tried it. We fired only one from the same batch of loads, it chronoed 824fps. Thanks for the reminder.

Appreciate the ideas. it helps me to keep thinking and learning.

[photog]

Possible causes of rounds that have extremely low velocity:

no crimp,

not enough crimp,

overall length way too long,

undersized projectiles,

oversized barrel,

wrong powder.

I'll wager on the crimp being the culprit. If you flare the case enough to load a lead projectile, you gotta make sure there is enough crimp. do this one of two ways. Some like me, like to seat the bullet with very little seating die crimp. Then I use a Lee Factory Crimp Die and give it a pretty heavy crimp. Be careful. too much crimp can spike pressures. Some just like to crimp and seat at the same time. That works too. I find the FCD works better.

I had this exact problem with a .45acp load. I started using the FCD and my problems went away. I was using American Select, which is very close in speed to TG. I think they are both double base. I called Aliant about it, they said it was the crimp. It has to do with the case volume and getting all the powder to ignite quick enough.

It does happen that projectiles can be undersized at the factory. Tap one through the barrel. If its fully deformed into the groves its probably ok. if it feels like it taps through too easy, the bullets could be the problem. They may have been mis-labeled, or they were made wrong. Murphy lives!!

My bet is the crimp.

[redmanfixit]

you may already know but it is a no-no to run lead in glocks with the factory barrel. be very careful. lots of glock have gone kaboom from running lead in polygonal rifled factory barrels. best.

liontribe

This has been covered a LOT. Glocks run lead just fine. The rules are well understood and a search of the forums here will reveal them. I have run THOUSANDS of rounds of lead thru my 21 SF no worries. No leading, no Kaboom!

The crimp is a good place to start. Pull tension (crimp) is a known effector on consistency and velocity. Also, what is the recommended load for titegroup in that bullet weight? There are plenty of instances in which too lite a bullet for a given propellant load will give erratic burn rates and low velocities. Slugging the barrel is a good idea to be certain. Having multiple sources of load data (I like OLD reloading manuals) written by smart old guys in addition to newer ones for the newer powders.

[RedHawk]

since the ammo shoots as expected in another gun, I think we can eliminate the ammo as the problem.

There is something about this particular bbl in his gun that is causing the problem.....my guess would be that the bore is oversize and the lead bullets are not generating enough pressure for complete combustion of the powder.