.45 ACP vs .45 Win Mag

[alamogunr]

I've been looking at my shell holders with a view to acquiring RCBS or Redding to replace some of my Lee holders. In looking at both catalogs, in the case of .45 ACP and .45 Win Mag, I find that different shell holders are specified for these two cartridges. Even Lee has a different shell holder for these two. Checking the drawings, they both have the same rim size. What could cause this?

[Piedmont]

Sounds like the groove above the rim is different diameter or depth.

[stubshaft]

I had a .45 mag barrel for a Contender and used my 45 ACP dies and shellholder to load for it. Didn't even think to look if it needed a special holder.

[alamogunr]

I guess that is what got me thinking. My .45 ACP Hornady dies also say .45 Win Mag but specify different shell holders. ??

[GONRA]

GONRA uses .45 ACP Shell Holder for both .45 ACP and .45 Win Mag Just Fine.....
As far as anyone can tell, .45 Win Mag is just an elogated .45 ACP.

[alamogunr]

Everyone has confirmed what I thought but when I saw different shell holders specified by different companies I wondered why.

In case anyone is interested, here are the specified shell holders from the respective catalogs:


.45 ACP RCBS-#3 Redding - #1 &#17 Hornady-#45

.45 Win Mag RCBS- #36 Redding- #7 Hornady - #1

And I'm not sure that these are the only shell holders specified. My Hornady .45ACP/.45 Win Mag die set shows #3 as the shell holder but I've had that set for several years and I've used the RCBS shell holder for both cartridges.

[Harter66]

The 45 ACP , Savage , 308 , Mauser , 06' brass families have at least 3 different , maybe 5 , rim/head/extractor groove specifications via CIP and SAAMI . Additionally as some of the cases above cycle age the extrctor grooves tend to narrow . Meaning that the groove gets closer to rim OD and narrower up and down also . The brass in the above families has rim dia from .470 to .478 with slightly different rim thicknesses . Some of these shell holders are cut specifically for the taller extractor groove , wider rims and deeper or shallower grooves , some like Lee are cut to take the widest rim shallowest and shortest groove . They will have the least rim purchase and the least absolute centering between the ram and dies .

Think of it like using a 38/357 shell holder for 7.62×39 , 40 S&W , and 6.8/25/30/32 Rem . It works but it's not right .

So the high value makers make a holder for 6.5 Mann , 7.65 ×53 , and 6.5×55 and another 45 ACP and 308 along with one more for the ×57 and 06' clans .