lordpaxman
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The case length doesn’t affect seating depth, assuming your COL and bullet OAL are constant. I don’t measure, and don’t trim taper crimp cases. Roll crimp cases I measure and trim if necessary.
QUESTION ON TRIM??
- Thread starter 74man
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The case length doesn’t affect seating depth, assuming your COL and bullet OAL are constant. I don’t measure, and don’t trim taper crimp cases. Roll crimp cases I measure and trim if necessary.
243winxb
Member
For best accuracy, everything needs to be exactly the same in your reloaded ammo.
Fl dies that size and maintain the case taper may come first. Carbide insert with a taper vs a sizing ring.
The "M" type expander is best. Brass is less likely to shave lead or coatings on seating. Bullets are seated straighter.
My new RCBS 9mm Luger die set has/does both.
Can you shoot the difference? Is your 9mm a spray & pray model? Or a finely tuned match gun?
My Taurus G3C doesnt know the difference between good and bad ammo.
GeoDudeFlorida
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I think the real question isn't trim, its volume, and IIRC (can't find it right now but I'm sure it's there) @LiveLife and a couple other of the testing gurus did some work on that subject and found that very minor differences in the CC water volume made almost no difference in pressure, velocity or accuracy but very large differences - on the order of some large percentage increase/decrease? - made enough difference to judge some higher and lower end loads unadvisable. Or, at least less accurate than could be gained with proper sorting, not necessarily by headstamp but by case volume and condition.
I still think neck tension and bullet concentricity are more important in pistol loads than case length but, I'm not an expert or even an amateur sleuth in that field.
I still think neck tension and bullet concentricity are more important in pistol loads than case length but, I'm not an expert or even an amateur sleuth in that field.
barnfrog
Member
In theory, wouldn't the longer case have slightly (infinitesimally?) more neck tension? Just a little more length of case holding onto the bullets bearing surface. I would think you'd have to compare max length to trim-to length to see any appreciable difference though, and can't imagine it would be enough to notice shooting offhand.
Engineer1911
member
I'm in a comfortable chair, popcorn is buttered and salted, a frosty cold one is at hand. Let the debate, OCD, search for perfection begin. Truth be told, Reloading is an Endured Activity so that Shooting may be thoroughly enjoyed.
Atavar
Member
Shorting is a necessary activity to support reloading.
BlackEagleSpeer
Member
Trimmed a few hundred 45 ACP's 2 years ago and I still regret it. They're up to about the 14th load now and they have just a little too much headspace. They do not grow back. If you're quite sure you'll be using the matched headstamp batch indefinitely and you want the most consistent crimp possible, you could figure out what your shortest case is and trim them all to that length, but that's time better spent with family, learning a new hobby, or practicing a low tech root canal in the mirror. They will never be perfectly cut enough and the precision of a taper crimp simply doesn't make us better marksmen.
I wish I could have read my own comment 20 months ago. I'll never get all those hours back. I just thought the dudes telling us not to worry about these details with pistol cases were just half-assin hicks. I lament and repent of my ignorance.
I wish I could have read my own comment 20 months ago. I'll never get all those hours back. I just thought the dudes telling us not to worry about these details with pistol cases were just half-assin hicks. I lament and repent of my ignorance.
BlackEagleSpeer
Member
Correct. The added friction of the extra .01" of brass is negligible. If you set the crimp tight for a shorter case, then it could be extra tight for the long ones that get pushed further in. Still not enough to be an issue with mid-range loads unless you really screwed something up beyond reason. It's the space between the bullet base and the top of the settled powder that matters here and these aren't affected by the case mouth getting a little shave.
Bcwitt
Member
I will be very suprised if you ever find an over length 9mm case.
BlackEagleSpeer
Member
Never in my life seen the fabled 9x21 in such abundance no has the 9x19 been so scarce that anyoneone was just like, "Damn, I gotta spend a weekend tryna make this work." Be a cool skit for Mad TV or something if our ilk hadn't been so under-represented in media. We had, what, Death Wish 3 and some Steven Segal movie once?
AJC1
Member
That old man eating an apple with a pocket knife knows some things...
Gator Opus
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- Jun 1, 2022
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Question for 308 reloaders. Have been shooting factory match grade for several years. Decided to try reloading them. Did a full length resize on 200 spent brass (all fired from my gun). When I measured the length of all 200, I found that about 15% were actually shorter than the recommended length (from 2.004 to 2.012). Has anybody ever seen this and do I need to discard these cases?
AJC1
Member
Most of my Norma cases on the first firing measure 2.000-2.005. They are just fine.
Blue68f100
Member
Have you checked to see if they fully chamber in your gun after resizing? If not set the sizing die lower and try again. They will grow a little longer if you need to move the shoulder back. I would not worry about brass being a little short. If your loading for max accuracy the odds are is that you will not be crimping.
armoredman
Member
Been loading 9mm for 17 years or so - I have yet to trim a single one. Rifle brass, sure, but the pistol brass will either break or be lost before they need trimming.
Engineer1911
member
Brass length is only problematic when case length exceeds max by more than 0.005". My loads are not max powder charges, resize 308 range brass with RCBS small base X-die. If the upstroke has significant resistance, Stop remove case, resize with conventional small base sizer die, and trim to minimum case length. "Close enough" works for case length as long as resized brass is not too LONG.
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Bcwitt
Member
A better thing to do is sort them by length. You find a headspace condition your gun likes/ dislikes
AJC1
Member
That's an oal not a base to datum measurement.... I'm not sure he has the tools for that measurement
Bcwitt
Member
I dont think your reading me. You can find a case legnth that delivers better groups. For example, my 45 is tightest w the longest cases i can find (usually .895) the shortest cases (.888) i reserve for blaster grade ammo. I also perfer the shorter case for lead bullets & the longer cases for jackets. If you really want to tighten things up, get some 45 win mag cases & trim them to where the gun will just lockup. Minimum headspace locates the cartridge perfectly.
AJC1
Member
Still not following as the 45acp indexes on the rim and the 458 on the shoulder... the only rifle I am aware of that works like that is the 350 legend, and I'm going to avoid that.
Bcwitt
Member
45 acp headspaces on the mouth. Not sure how to index rim on a rimless case. Might want to look @ those case drawings again.
AJC1
Member
Semantics as like I said 45acp and 350 work the same... is that incorrect or is this a vocabulary battle...
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