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donS
12-01-2009, 07:55 PM
I picked up a lot of once fired brass and started to sort it for trim length. it is 45 acp and the over all length is suposed to be max .898. well i got some rediculous variations from .890 ( the biggest I found ) to a small size of .870. that seems like a very large variation since this case headspaces on the trimmed end and almost 1/32 short seems like too much. Any ideas on the max under for trim length.
Don S

zomby woof
12-01-2009, 08:05 PM
I've never trimmed .45 acp. Stop looking at them and they'll shoot just fine.

mpmarty
12-01-2009, 08:16 PM
I've shot 45acp since 1957 and never trimmed a case. They eventually neck split but they NEVER need trimming. If in fact they really headspaced on the case mouth none of them would work right. My reloads headspace on the boolit resting on the throat taper into the lands.

Kskybroom
12-01-2009, 08:27 PM
I get brass from a indoor range,(Lots) Ive never trimmed 45 acp brass. Reload them 3 times let'em fly. Reloading for a short range combat pistola isn't the same as a long range rifle? Load'em by the pail an let'em fly.... (ie FUN) ....

donS
12-01-2009, 08:43 PM
the .45 acp headspaces by design on the end of the case. that is why we are not suposed to use a roll crimp. a taper crimp is ok if not overdone.
the small length cases i found will have a 1/32" gap between the face of the slide and the end of the case when it is pushed foreward by the fireing pin and then fired and the case will have to slide to the rear or stretch or maybe have a head separarion. I cant believe these cases were designed to function this short but I cant find a mimimum trim size.
setting the bullet out far enough to engage the lands may work but the ammo will be custom for that gun and may not work in another weapon.
Don S

badgeredd
12-01-2009, 08:49 PM
I picked up a lot of once fired brass and started to sort it for trim length. it is 45 acp and the over all length is suposed to be max .898. well i got some rediculous variations from .890 ( the biggest I found ) to a small size of .870. that seems like a very large variation since this case headspaces on the trimmed end and almost 1/32 short seems like too much. Any ideas on the max under for trim length.
Don S

I seriously doubt your brass is "once fired" because of the lengths you mentioned. The .890s are likely ONCE fired but the short ones at .870 have likely been resized at least three times. 45 ACP brass shortens with sizing. As mentioned, if you load long enough to function and can have the bullet rest in the throat you're good to go. Never have trimmed any ACP brass either. Use it till it isn't any good anymore.

Edd

donS
12-01-2009, 09:04 PM
I shoot two bullets one a 230 grain hollow point full power for plinking, practice and self defense. the other is a 200 grain semi wad cutter target load. the first I can load out to contact the lands but the SWC is loaded about flush with the case end and wont come close to touching any lands. All the target loads seem to be using this or similar bullet,

Don S

mike in co
12-01-2009, 09:06 PM
untill last month i had never seen a 45 case anywhere near the listed spec...it has always been shorter, and sometimes a lot shorter.

i have trimmed brass for 45 acp. uniform lenght means uniform crimp. uniform lenght may mean uniform ignition IF your gun actually headspaces on the case mouth. i measure a bunch and trim to the low end of the batch and go with that.


last month i found a single lot of mil '62 match ammo that is actuall slightly longer than spec!first time in 10 years of loading for 45 acp.


mike in co

Bullshop Junior
12-01-2009, 09:12 PM
I would just shoot them.

lwknight
12-01-2009, 10:52 PM
I agree to just do not look at the case length. Just use them.
This includes 9mm and 40SW too.

For some reason those type cases never need trimming and there is nothing you can do for the shorties.

yondering
12-02-2009, 12:07 AM
the small length cases i found will have a 1/32" gap between the face of the slide and the end of the case when it is pushed foreward by the fireing pin and then fired and the case will have to slide to the rear or stretch or maybe have a head separarion. Don S

This is fine. Try them, they won't give you any problems.
You won't get case head separations either. This is the 45 ACP, not a 308. Pressure in the 45 is about 1/4 that of a 308 or many other high powered rifle cartridges.

Don't worry about it, just use them; if you're like the rest of us, there's plenty of other things to worry about in this life.

Echo
12-02-2009, 12:19 AM
the .45 acp headspaces by design on the end of the case. that is why we are not suposed to use a roll crimp. a taper crimp is ok if not overdone.
the small length cases i found will have a 1/32" gap between the face of the slide and the end of the case when it is pushed foreward by the fireing pin and then fired and the case will have to slide to the rear or stretch or maybe have a head separarion. I cant believe these cases were designed to function this short but I cant find a mimimum trim size.
setting the bullet out far enough to engage the lands may work but the ammo will be custom for that gun and may not work in another weapon.
Don S

This has been gone over before. NO .45 case is long enough to reach the end of the chamber. My gurus told me to seat my boolits out maybe .030 - .040 from the case neck so as to contact the rifling origin. This stops end-play, and makes for more reliable ignition.

These gurus have all gone to their reward, but they built guns for National and World Champions, so I listened to them.

Marlin Hunter
12-02-2009, 12:51 AM
I've never trimmed .45 acp. Stop looking at them and they'll shoot just fine.


+10

:bigsmyl2:

DLCTEX
12-02-2009, 01:04 AM
My Lyman Cast Bullet manual gives max. case length as .898 and trim length of .895.

243winxb
12-02-2009, 10:58 AM
My Lyman Cast Bullet manual gives max. case length as .498 and trim length of .495. Hey Dale, i am sure you wanted to say .898" max. Trim to .895" RCBS lists both at .898" No Trimming. [smilie=s:

wallenba
12-02-2009, 11:51 AM
I go by the "trim to length", usually .888. But I like to square up the case mouths first and by the time I get that done I'm just a bit shy of that too, about .885. It does not seem to make much difference in my loads as my 1911 seems to space off of the extractor and my 625 uses the moon rings. As long as the O.A.L. gives the correct case volume by seating depth it works.
Those with convertible Ruger .45's though, might need it spot on.

DLCTEX
12-02-2009, 08:57 PM
My bad, correction made. Thanks!

donS
12-02-2009, 09:49 PM
when the firing pin moves foreward it is going to push the loaded round ahead till it reaches something to stop it.
Then the pin will begin to depress the primer shell. If you are shooting target competiion uniform ignition is important. great variation in case length will give differences in the firing pins ability to give uniform ignition to the powder charge. So I guess it depends what you out of your $1500 Match grade 1911. do you strive to shoot all X's or just make noise. I am looking to match the accuracy of a Browning Medalist and a Smith 52. I need to remove all the possible variation from the wepon ammo combo since i need all the help I can get In the case of the semi wad cutter the case will reach the end of the camber an not stop on the slug due to the shape.
I was hoping to get some more usefull and thought out answers. when I get the answers I need I will post them here for any one interested in a more scientific answer.

Don S

Echo
12-03-2009, 01:53 AM
Well, you could go to the gunsmiths that prepared .45's for national and world champions, and ask them what they thought re trimming and headspace questions. They had to produce, so the marksmen's scores could not be dependent on the quality of their accurizing. Bob Day had some run-ins with T.D. Smith, but then T.D. was national and world champion. I'm sure the Army, Navy, and Marine armorers had the same pressure. I feel confident that armorers that dealt with champions HAD to know their stuff. And all the pistolsmiths I dealt with (and they fit the above description) agreed re headspace and endplay.

Or one could simply read a Lyman, or Lee, or Speer, reloading manual and take everything in it as gospel...

Personally, I have never trimmed a .45ACP case, and never intend to. I seat my booits out from the mouth and taper crimp, and am a happy camper.

armyrat1970
12-03-2009, 07:52 AM
Cast boolits? I'm sure we have all made the same mistakes but shouldn't this be somewhere else?

Well. After reading many other post I guess I have to retract my above statement.

243winxb
12-03-2009, 09:43 AM
I picked up a lot of once fired brass This is your first mistake. World Class shooters of the 45acp in bullseye competitions don't "pick up" brass.
setting the bullet out far enough to engage the lands may work but the ammo will be custom for that gun It does work with lead bullets if the barrel is chambered for this method to work.
I need to remove all the possible variation from the wepon ammo combo Then you should not be posting on a "cast bullet" forum. We all know that cast can have air/gas bubbles, unseen inside the bullet. At 50 yards the X ring is about 1 5/8" in diameter, no master or High Master class shooter is going to shoot casted. IMO. Unless each and every bullet is weighted.
There is a lot of poor info in the replys You ask simple questions, you get simple replys. "NO TRIMMING IS NEEDED" for your brass. If longer than .898" then you may want to trim.
Any ideas on the max under for trim length. When you find out what is to short, let us know. I would guess misfires would be the first clue.[smilie=l:

lwknight
12-03-2009, 11:10 AM
Ditto the above:
Don if you want match quality brass, go buy some. Picking range brass is hodgepodge and most don't care. Auto pistols are not exactly snipe rifles anyway.

rob45
12-03-2009, 12:04 PM
I absolutely love the 45 Auto. Especially in a 1911.

I find it interesting that the extractor claw might serve an additional purpose (besides extracting).

Just some food for thought for those who wish to think outside the box.:idea:

Char-Gar
12-03-2009, 12:24 PM
My thoughts on the issue at hand;

1. I have fired hundreds of thousands of 45 ACP reloads and have never trimmed a case. This included huge numbers of match ammo.

2. You have discovered that autopistol cases,ceven of the same make, vary in length. Not a big secret, but disconcerting when made evident to the shooter. 9mms vary as well.

3. If you are not trying to loads ammo for high level of competion, then disregard the difference, load and shoot.

4. If you are looking for the untimate in accuracy (i.e. small groups), then sort the cases by make, lot and length. Load them in batchs of the same length and you will see a slight improvment in group size.

I guess that is it for me and this thread. Good shooting!

243winxb
12-03-2009, 02:12 PM
I find it interesting that the extractor claw might serve an additional purpose (besides extracting).The extractor may or may not help control headspace, long time disagreement on that one.:confused: The firing pin in 1911 & S&W 645 autos are inertia type firing pins. They have a lot of travel, there is no firing pin stop like on some guns.
FIRING-PIN, INERTIA
A type of firing-pin in which the forward movement is restrained until it receives the energy from a hammer blow. It is slightly recessed in the breech face before being struck by the hammer and is shorter in length than the housing in which it is contained. Upon hammer impact, it flies forward using only its own kinetic energy to fire the primer. What i do know is, soon or later the firing pin will make contact with the primer in the guns i have listed. This is with normal brass. Brass that is at maximum length of .898" seems to be the most accurate, but hard to find or buy. Do a test, load a light target load with 3 brass. After each firing, trim off .010", let me know how short the case is when you get a misfire. Its going to be very very short IMO. [smilie=l:

Char-Gar
12-03-2009, 03:32 PM
Win243 ... Re: World class bulleye shooters don't pick up brass.

1. I am not nor ever have been a world class shooter of anything.
2. In the days of yore I did shoot Bullseye and did so pretty well with a good ranking.
3. In practice, I picked up every 45 ACP case I could find.
4. There were no sponsors in those days and we had to make every nickle county.
5. The exception were the military shooters who were financed by our tax dollars.
6. I used new or 1X fired brass for matches and each case was inspected with great care.
7. I darn sure would have picked up those cases at a match, but match rules won't allow that due to time constrainst.