case trimming

[marquitos]

Hi, I`ve been reloading for a couple of years, and noticed that my .44mg cases were unevenly long, resulting in different crimping etc.
most literature I`ve read says:max. trim length 1.275, and I have cases that mike at 1.270 different brands.
How short should one trim?
thanks in advance, mark

[Chuck White]

almtnman
I disagree!
Pistol brass and other straight wall cases do need to be trimmed!

Straight wall cases require trimming in order to get a consistent crimp!
If the case lengths are different, you can't get a consistent crimp!

The max length for 44 Magnum cases is: 1.285 inches.
The trim length for 44 Magnum cases is: 1.275 inches.

[Graybeard]

almtnman
I disagree!
Pistol brass and other straight wall cases do need to be trimmed!

Straight wall cases require trimming in order to get a consistent crimp!
If the case lengths are different, you can't get a consistent crimp!

The max length for 44 Magnum cases is: 1.285 inches.
The trim length for 44 Magnum cases is: 1.275 inches.

So say you and some others. I've been reloading them for about 35 years at least and have yet to trim a straight wall case. Don't see me ever doing it in this life time.

[gypsyman]

Been loading for over 30 years, I believe in case trimming, especially, in straight wall cases. Had bullets pull out, and lock up a revolver, because the crimp was inconsistent. Ran loads over chronygraphs, always more consistant with trimmed and crimped brass. Guess it's what ever works for you. Gypsyman

[Almtnman]

almtnman
I disagree!
Pistol brass and other straight wall cases do need to be trimmed!

Straight wall cases require trimming in order to get a consistent crimp!
If the case lengths are different, you can't get a consistent crimp!

The max length for 44 Magnum cases is: 1.285 inches.
The trim length for 44 Magnum cases is: 1.275 inches.

Explain to me and others on the forum what would make a straight wall case expand in length. I know that a rifle case when it's full length resized will expand in length when it's fired because the bell of the case moves forward. When I neck size rifle cases, I very seldom have to trim them back as the bell of the case is up against the chamber and there's no where for it to expand anymore. I just can't see why a straight wall case will expand out longer when there's no reason for it to do that. When it's fired, it opens the crimp and lets the bullet be on it's way, but the case wall is not moving forward like a belled rifle case does.

If I have my .44 mag cases all set at 1.285 inches long and load them up and fire them, how long will it take for the length to expand out any farther than that?

[stuffit]

You certainly can (and I did) reload for a long, long time and never trim straight walled brass.  However, I don't think anyone is going to argue that they have not encountered brass of this type of lengths varying enough to make consistant crimps "iffy" if not unobtainable, and the process of trying a pure aggravation, even when crimping is done in a separate step from seating.
Now some might argue that consistant neck tension doesn't contribute to better accuracy and that consistand length isn't necessary to get the consistant crimp  needed to get even neck tension an a batch of reloads.  But, to my notion, they'd be wrong.  If you want consistant bullet release (the same neck tension in a batch of loads) you have a couple of choices.  You can get your micrometers out and sort them by length or you can trim them to a standard length.  What I've run into brass manufaactured by the same maker, collected over the years, from various sources, that is of widely varying lengths (enough to make crimping a pain, anyway).  And often the shortest length (this is in brass never before trimmed) is less than the recommended "trim-to" length.  My expedient has been to trim to this "lowest common denominator" when I'm making up a batch of loads that I want maximum consistancy in as many parameters as can be controled.  It seems to work.  Admittedly, new brass, every time , might accompllish this better, but trimming saves bucks and it makes for better reloads.   And don't even start on mixed batches of brass.  There's enough variability of length to make a preacher cuss.  Bottom line - if you want consistant crimps and neck tension, you gotta trim. 
 
stuffit

[GregP42]

Well, I have had to trim straight walled pistol cases, but I am talking full house 60 rounds and your done for the week of shooting silhouette loads out of a .41 mag. But even with loads like that I would only have to do it after maybe 7 or 8 firings, and the brass was mostly trash after 15 to 20 reloads. Now one round I have had to keep an eye on and maybe trim every other loading was 32-20, but then they were also loaded with very heavy bullets for silhouette shooting and if they made it to 6 reloads it was a miracle.

Now new brass I will trim, but that is only so they are all the same length, under normal shooting I very seldom have to trim brass. Well that is my 2 cents worth.

Greg

[Almtnman]

You certainly can (and I did) reload for a long, long time and never trim straight walled brass.  However, I don't think anyone is going to argue that they have not encountered brass of this type of lengths varying enough to make consistant crimps "iffy" if not unobtainable, and the process of trying a pure aggravation, even when crimping is done in a separate step from seating.
Now some might argue that consistant neck tension doesn't contribute to better accuracy and that consistand length isn't necessary to get the consistant crimp  needed to get even neck tension an a batch of reloads.  But, to my notion, they'd be wrong.  If you want consistant bullet release (the same neck tension in a batch of loads) you have a couple of choices.  You can get your micrometers out and sort them by length or you can trim them to a standard length.  What I've run into brass manufaactured by the same maker, collected over the years, from various sources, that is of widely varying lengths (enough to make crimping a pain, anyway).  And often the shortest length (this is in brass never before trimmed) is less than the recommended "trim-to" length.  My expedient has been to trim to this "lowest common denominator" when I'm making up a batch of loads that I want maximum consistancy in as many parameters as can be controled.  It seems to work.  Admittedly, new brass, every time , might accompllish this better, but trimming saves bucks and it makes for better reloads.   And don't even start on mixed batches of brass.  There's enough variability of length to make a preacher cuss.  Bottom line - if you want consistant crimps and neck tension, you gotta trim. 
 
stuffit

I can see what you mean when you have case lengths of all different lengths. You wouldn't want to start crimping bullets in them when they were different. But the question is this; when you trim those cases back to the shortest length so they are all the same length, how many times can you fire them before they need trimming again? And how much are they going to expand in length after being fired? What would cause a straight wall case to expand in length?

[Almtnman]

Now new brass I will trim, but that is only so they are all the same length, under normal shooting I very seldom have to trim brass. Well that is my 2 cents worth.

Greg

I think that's (normally) what I stated in my first reply also. 

[Chuck White]

almtnman and Graybeard
To trim or not to trim is ones own choice.

I'll bet if you were to measure all of your straight wall brass, you will find many different lengths!

I guess what I'm trying to say in a nutshell is "if your brass isn't all the same length, how do you expect to get a uniform crimp"?

I'm not saying that I trim my brass all the time, but if I pick up some new or once fired, I will definately check it and if necessary, trim it!

NOTE: If trimming is not necessary, then why does RCBS include it in Case Preparation instructions that come with every set of reloading dies?

[stuffit]

I can see what you mean when you have case lengths of all different lengths. You wouldn't want to start crimping bullets in them when they were different. But the question is this; when you trim those cases back to the shortest length so they are all the same length, how many times can you fire them before they need trimming again? And how much are they going to expand in length after being fired? What would cause a straight wall case to expand in length?

I don't know if they do.  I don't shoot as much as I once did and I'm not really sure what the factors were that led to the variation in length in brass from the same manufacturer (mostly WW or Rem/UMC).  I suspect they were manufactured that way.   I've paid more attention to detail in my reloading since retirement.  So far, since I started trimming all my pistol  (mostly 44 mag)  brass to a uniform length before beginning the process of reloading it, I've not found it necessary to trim  them again.  So far.......
 
stuffit

[Almtnman]

almtnman and Graybeard
To trim or not to trim is ones own choice.

I'll bet if you were to measure all of your straight wall brass, you will find many different lengths!

I guess what I'm trying to say in a nutshell is "if your brass isn't all the same length, how do you expect to get a uniform crimp"?

I'm not saying that I trim my brass all the time, but if I pick up some new or once fired, I will definately check it and if necessary, trim it!

NOTE: If trimming is not necessary, then why does RCBS include it in Case Preparation instructions that come with every set of reloading dies?

I'm like you, I check it and if it needs trimming, I trim the cases all the same. After that iinitial trimming if it needed it, I find that the case lengths in straight wall cases normally don't need to be trimmed after that. I can get a lot of loads without any expansion. I would suspect that if someone is shooting loads in a match chambered pistol or rifle, it might be important to check length size, but under normal shooting conditions trimming a straight walled case each time is normally not needed. This has been a very good debate on trimming and I have throughly enjoyed everyone's input on it. 

I had to come back and modify this post as I noticed some of your quote was in the message that I must have missed when I replied about RCBS include it in Case Preparation.

I didn't say that trimming wasn't necessary, what I said was normally straight walled cases don't have to be trimmed. I guess that in my initial reply I didn't get far enough into detail and it didn't come out on what I wanted to say by typing it out. What I was implying was, once the cases are the same length, if they are straight walled cases and you load them up, then normally they don't have to be trimmed after that or not for a lot of firings anyway. Depending on how hot I load depends on how many loads I can get out of a brass case. Loaded up with hardcast target loads, I might get 20, 30 or 40 loads out of a case. Loaded up with full house loads, I might get 3 to 5 loadings.

[Don Fischer]

I have never trimmed a straight wall pistol case. But after reading this tred, I could see how it could help. Probally if you measured all your cases and trimmed everything to the shortest case you'd get better ammo. Also someone mentioned squareing up the case mouths, might be a good idea. Now I'll go back to not trimming, handguns are just for plinking for me!

[Bullseye]

Well I have trimmed straight wall cases before because they have stretched to a length longer than the Max length in the manuals.  Now this generally takes more than 5 or 8 loadings on a case opposed to 3 or so with bottle neck cases, but I have seen them grow to a length longer than the max so I trimmed them.

[gwindrider1]

Gentlemen,

This is not pertinent to straight walled revolver cases, but let me say that the cases for my .458 Win. stretch more per firing than any bottle necked cartridge I have ever loaded for.  It is unsound thinking to believe that straight walled cases don't stretch.

[marquitos]

Never expected such a response!! Thanks all for your input, its the first time I trim, matter of fact! but I`m still bemused by the fact that if most specs. say max trim length 1.275 how come there is brass that is even shorter? even when its been reloaded plenty.
Again thanks all, its been most enlightening, mark

[marquitos]

Never expected such a response!! Thanks all for your input, its the first time I trim, matter of fact! but I`m still bemused by the fact that if most specs. say max trim length 1.275 how come there is brass that is even shorter? even when its been reloaded plenty.
Again thanks all, its been most enlightening, mark

[Chuck White]

marquitos
The MAX  length is 1.285"
The TRIM length is 1.275"

If you have brass that is shorter than 1.275", possibly someone had it before you and over-trimmed it!
If it's really short, maybe it's 44 Special brass!

[marquitos]

Nay, its 44mag. brass, but I`ll check them out, and tell you what brand.