I recently had to clean out my father's ammunition storage locker (RIP Dad). He shot for years on a Navy team and would frequently buy surplus ammo. I found about 500 rounds of old M1911 ball ammo circa 1955. Half is by Remington Arms that looks and shoots normal (on right in pic). Some is manufactured by Olin Mathieson Chemical Corp. and has a weird crimp around the middle of the cartridge (on left in pic). This Olin stuff does not cycle well in my 1911 (Wilson Combat mag & stainless match barrel).

Any thoughts on why the crimp????????

THANKS

It's called a case cannilure and it helps prevent the bullet from being pushed down deeper into the case.

sorry for your loss.
A fair amount of 45 ammo used to have some type of crimp there behind or near the base of the bullet .

I would guesstimate the military wanted it to make 45apc ammo more rugged for sub gun use and since the loading machines built during the war were set up like that the ammo companies just kept cranking it out.

Have you run any of this ammo over a chronograph?  I have run across some "factory match" ammo that was loaded a bit slower . It ran fine in most guns but was a bit fussy if some guns were not clean and all lubed up. It was a bit more accurate if I did my part. I would also think your Wilson chamber might be a bit tighter that a stock Colt barrel .

I have been involved in cleaning out the reloading room/ammo stash of several late gun club members . Kind of a bitter/sweet kind of thing .
Hate to have someone pass but the cheap skate in me loves the good deal . I got a good deal of ammo and components from one gentleman
in particular who was a great competitor and it tickles me to shoot his ammo at a club match and do well enough to tell the guys that they have been beaten by Howard's ammo .

You can be sure I have left instructions with my family to get any of my stuff down to the club if anything should happen to me

Thank you so much for the information. I have learned something new today.

My heart is heavy that I was never able to ask my father about these details while he was alive

At the same time, I cherish everything that I found while going through his possessions.

If I have learned anything from this experience, it is to share my family and personal stories with my children while I still can!

Thanks again for the information!

I have 45acp (read WW2 / Korean war era ) stuff as well as another can of 1000 head stamped WCC 1971 that my dad left me. A little over 2500 rounds. It is hot, has a cannelure and old black tar primer sealer. I shoot it in my 1945 Remington rand 1911 and my other Colt and Ruger 1911's. No reliability issues in about 300 rounds fired.

As for your Dad passing my condolences. Mine passed in 2005. I often take my 3 sons into my office where my safes are and share my Knife, watches, guns ,jewelery, coins  and camera collections with them. This way when I go on to that big farm in the sky with my Dad, grandpa, Mom , Grandma , etc my boys have a clue and then some to my contents and its history. Being only 43 I have a lot more stories to tell.

It could be match ammo and the Olin might be loaded milder, requiring a softer recoil spring. My guess would be its good non-corrosive ammo. Depending on storage conditions, it could be right up to original spec, and certainly looks the part.