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Another Reloading Question


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#1 JimFromFL

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Posted 09 January 2004 - 11:13 PM

What overall length do you use?

My reloads were working fine until I replaced the barrel with a repro barrel.

Now it appears feeding of the reloads are causing a problem. Factory ammo appears to be working fine.

Apparently with Clays powder the overall length is supposed to be 1.200 which i think is too small.

I went as small as 1.240 and this caused numerous jams. It appears that the bullet nose would catch on the lip of the barrel and cause the bolt to stop about 1/4 inch before closing and actually create a small indentation in the brass.

I tried some at 1.260 and this was a bit better but there were still some problems. These failures seemed to cause the bolt to slow down and prevent the firing pin to hit the primer hard enough.

Keep in mind all worked fine before the new barrel and recently installed a new firing pin and spring for the bolt.

The next step would be to try about 1.250 and 1.230 lengths to see if there are any improvements.

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#2 Bisley45

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Posted 10 January 2004 - 01:42 AM

My relaods are 1.260 +/- .005 always worked fine. I miced some of my comercial stuff and it was between 1.253-1.257
Miced some of my old military and it was 1.268-1.271, made in 42 and 43. only checked about five rounds each, hope this helps.

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#3 PK.

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Posted 10 January 2004 - 09:09 AM

SAAMI shows 1.200-1.275 for ball.

It sounds like you have a geometry problem with your barrel; most every repro I install needs to be touched up to bring into print specification for proper function.

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#4 john

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Posted 10 January 2004 - 06:32 PM

Jim,
a couple points. Overall length shouldn't cause rounds to stick in the chamber, not denting enough to fire. Sounds as if you have a problem I experienced a few years ago.

I reloaded a bunch of .45 for the Thompson I would later buy. Loaded up to specs the former owner gave me. I think the OAL was 1.260, but not sure. Load was W231 (5.6 gr??) with a 230 Gr, ball projectile, wlp primers.
At any rate, a few would fire, then one would stick in the chamber, not quite going far enough forward to fire. Some of these "chamber stickers" would pop right out and others required substantial rearward force with a 2x4 to extract them.....these would pop out with scrape marks on the front edge of one side of the brass casing.
Some would stovepipe as if the front edge of the bullet was hitting the top of the chamber and didn't go in. None of these stovepipes chambered properly later.....
The mystery was solved at a later date when another Tommygunner asked me if I had used once-fired oistol brass to load up this ammo. Hmmmmm....that turned out to be the case, and when fired in a pistol there is a bulge on one side of the brass just ahead of the rim.
When I sized these with Rcbs dies, the bulge remained!!

I talked to a local reloader and they recommended Lee dies that resize and gauge the entire round as the bullet is seated.

Ammo loaded with these runs great, using once-fired pistol brass OR once-fired Thompson brass.

Of course, you can use brass that was fired in a Thompson (no bulges!!)
but give the Lee dies a shot....might work ok??

let us know if this works for ya!

john
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#5 Whiskey Brother

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Posted 10 January 2004 - 11:37 PM

You may want to buy or fabricate a gage to check your reloads with. Sometimes if you have the bullet cocked off to one side when you seat it, it will bulge your case out on one side. Try to be as exact as possible when seating the bullet, as it sounds like your new barrel has slightly tigher specs than the old barrel. Since factory is working fine in your gun, this is my best guess...
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#6 JimFromFL

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Posted 11 January 2004 - 09:09 PM

Thanks for all the good info.

After reloading I check each round with a .45 gage and only use the ones that drop in and slide right out without problems.

The next step for me is to try 1.250 and 1.220 for the length.

I will keep you all posted on the results.

Thanks again.

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#7 21 smoker

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Posted 11 January 2004 - 09:38 PM

JimfromFL,...I do the same with my reloads,..check them with 45 gauge,.. I load on a Dillon 650 with Dillon sizing die,...that seems to clear my malfunctions in my 21 due to ammo. Any rds. that don`t drop in easy I run thru mac10 p.s....that digests anything! It amazes me ... all the crap we heard for years about macs and it is the most reliable FA 45 I own...just uncontrollable for a whole stick... 1.260 seems to work the best for the inventory,5.0grs of Bullseye,230gr.rn lead or fmj....clean up seems better with Bullseye and less powder wt....my .02 out.
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