testtest

headspacing

TEXASforLIFE

TEXASforLIFE

Ronin
Most cases are trimmed .010" less than max case length. Well going thru Hornady's manual at 44mag using 225ftx bullets you are required to trim @ 1.255" which is .020" less than max. Don't forget these are straight wall cases that headspace off the mouth. 20 thou isn't much, so lets go onto 45-70. Hornady again, but with 325ftx requiring case be trimmed @ 2.040". That's 55 thou off trim length and 65 thou off max case length. They've been safe to shoot, but haven't thought about headspace. I guess taper solves it? Hornady's reasoning for case being shortened is due to bullet seated deep. Fair enough! Still, what's up with headspacing?
 
The 44 Magnum head spaces on the rim.
(also 25 Automatic, 32 S&W, 32 Federal Mag., 32 Automatic, 38 S&W, 38 Super / Auto, 38 Special / 357 Mag, 44 Special, 45 Auto rim, 45 Colt and most rimmed pistol cartridges.)



Centerfire Pistol and Revolver Ammunition

45-70 also headspaces on the rim-

CARTRIDGE AND CHAMBER DRAWING 45-70 GOVERNMENT


I see that both the 44 225 gr FTX and the 45 325 FTX have a cannelure on the bullet, does the trim to length and the Hornady OAL length put the cannelure at the end of the case / for crimping?
 
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44 mag due to the power of the round requires a stout roll crimp to prevent bullet creep especially in revolvers. I use a Lee factory crimp die on all my 44 mag rounds which could end up in either my Model 29 or Winchester 94.
 
Yes most rimmed straight walled cases headspace on the rim. I believe Hornady directs reloaders to shorten cases for FTX bullets due to the bullets long ogive. I.e. keep c.o.a.l. within max. This ensures the cylinder will turn in revolvers and proper feeding in lever guns. This is something to keep in mind if buying factory loaded Hornady FTX loads. The cases are shorter and must not be used when reloading for other data.
 
Some of the Bullseye shooters as far back as the early 60's sleeved 38 super chambers so they would headspace off the case mouth instead of the rim, many Colts in that time had excessively long chambers affecting accuracy.

The current SAAMI specs show head space on the rim for the 38 super.
 
The SAAMI drawing stays consistent with the original and for the old pistols, but that doesn't keep the industry from changing the headspace to the case mouth. The case specs all stay the same.

Colt started head spacing 38 Supers on the case mouth with the "Super Elite" limited production model (essentially a 38 Super Gold Cup). In the early 70's Bar-Sto started doing that, and combined basically all makers do it that way now.

www.thegunmag.com

Rock Island Armory’s .38 Super 1911 - TheGunMag - The Official Gun Magazine of the Second Amendment Foundation

by R.K. Campbell | Contributing Editor The .38 ACP Super is easily our least popular handgun chambering that is still in production. Just the same, many thousands are in use with a small but dedicated group of fans. The history of the .38 Super is a thrice-told tale. (Fans refer to the cartridge...
www.thegunmag.com

 
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