senecahornet
New member
Started shooting my pieta 71/2 . Seems to me some of my cases will need to be trimmed. Right now they have been fired 3x and reloaded. Is this typical for the 45 colt ? Winchester & starline brass.
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Case length for 45 colt
- Thread starter senecahornet
- Start date
I have never had to trim a straight wall handgun case.
+1. Totally unnecessary.
Don
NoSecondBest
New member
Agree on not trimming straight walled pistol cases. The question is, why do you think they need trimmed? If you're having trouble with bullets rotating in the cylinder, you're not seating them deep enough or you don't have any crimp and they're moving on recoil.
senecahornet
New member
Thanks one and all for your replies.
max trim length for 45 colt is 1.285 in. when i re-sized in my lee die....
starting lengths are measured before they are run thu the die
and finish lengths are measured.
there is definite stretching of the case on the average of 0.010 to 0.015 inches
so if i start with a case that is 1.265 and end up with 1.280, next time i might have to trim.
And i am even lubing the cases, even though not necessary to do so.
Are you saying that because the cartridge seats on the rim and not the neck it does not required case trimming??
max trim length for 45 colt is 1.285 in. when i re-sized in my lee die....
starting lengths are measured before they are run thu the die
and finish lengths are measured.
there is definite stretching of the case on the average of 0.010 to 0.015 inches
so if i start with a case that is 1.265 and end up with 1.280, next time i might have to trim.
And i am even lubing the cases, even though not necessary to do so.
Are you saying that because the cartridge seats on the rim and not the neck it does not required case trimming??
I have been reloading revolver ammo since 1969. I may have measured some cases in the beginning, prolly out of curiosity, but have never needed to trim any. I started with cast led bullets that had a crimp groove and seated the bullet to the crimp groove (and the cannalure on jacketed bullets) and disregarded book OAL. Never had a problem...
NoSecondBest
New member
[QUOTEAre you saying that because the cartridge seats on the rim and not the neck it does not required case trimming?? ][/QUOTE]
I think everyone's telling you that they get longer after going through the size die and get shorter after firing them and they stretch to meet the cylinder wall. It's a cycle. Sizing makes them longer and shooting makes them shorter. Over time they don't stretch enough to require trimming. I've been loading straight walled cases for fifty years and have a lot o them that have been reloaded many, many times. They don't need to be trimmed.
I think everyone's telling you that they get longer after going through the size die and get shorter after firing them and they stretch to meet the cylinder wall. It's a cycle. Sizing makes them longer and shooting makes them shorter. Over time they don't stretch enough to require trimming. I've been loading straight walled cases for fifty years and have a lot o them that have been reloaded many, many times. They don't need to be trimmed.
Yep, my experience as well. Never trimmed a revolver case and I just crimp in the crimp groove. I have reloaded some cases many many times (20+) before tossing due to split mouths or splitting down the side. Been reloading since the early 80s BTW.... {edited} Lately I decided to trash all the old brass and start fresh again. All new Starline brass for the most part. Why? Because I want to. No other reason.have never needed to trim any. I started with cast led bullets that had a crimp groove and seated the bullet to the crimp groove (and the cannalure on jacketed bullets) and disregarded book OAL. Never had a problem...
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Max case lengths will be given in your manual. As will the trim-to even though it's highly unlikely you'll ever need to trim any hand gun case. And 3 times loading is really not that many. A handgun case is very, very unlikely to stretch at all. Never mind 20 thou in three loads.
Anyway, SAAMI Max is 1.285"(not "max trim length") with 1.265" being minimum. Quickest way to check case length is to set your vernier at the Max and use it as a case gauge.
Anyway, SAAMI Max is 1.285"(not "max trim length") with 1.265" being minimum. Quickest way to check case length is to set your vernier at the Max and use it as a case gauge.
Jim Watson
New member
I trimmed a bag of .357s so as to get a uniform roll crimp.
reloader28
New member
I always trim mine the first time to get everything the same length and consistant. Sometimes theres a huge difference in lengths.
One of the best answers yet...Why? Because I want to. No other reason.
Senecahornet,
The reason high power rifle cartridges need trimming is their peak pressure is high enough to stick the brass body to the chamber while the head is pushed back to the breech face, stretching the brass at the pressure ring where it transitions from thin to thick near the head. One reason this happens is the speed and magnitude with which the pressure builds and the other is that a bottleneck rifle case has the shoulder pushed against the chamber, helping to resist having the whole case move back before the pressure reaches the sticking point. Straight wall cases don't have that, so they need higher pressure to stick to the chamber to stretch than bottleneck cases do. The transition pressure, where sticking begins for bottleneck cases is usually around 30,000 psi peak. For straight-wall cases, it is often closer to 40,000 psi. Your 45 Colt is not at high enough pressure to grow brass.
In a case that has stretched where the pressure ring winds up, the increase in length occurs during resizing as the body is extruded narrower, pushing the brass at the front of the case forward. In a case that has not stretched at the pressure ring location, the whole case has backed up to the breech of the chamber, bringing the mouth with it. When that occurs, the whole case expands outward to seal the chamber against rearward gas leaks, and the brass to provide that extra width is acquired the opposite way from how the sizing die squeezes a case longer; it is done by pulling the case shorter. So, when you measure a fired low-pressure case from a chamber that had any wiggle room when you chambered the cartridge, it will be shorter than it was when you loaded it. When you resize it, the sizing process is merely putting the brass back in place...assuming it can.
I once ran some bulk-purchased 45 Auto brass through 50 light target shooting reload cycles. Just under 1/3 were left by then, the rest having split or been inadvertently sacrificed to the range gods. After resizing straight-sided with a Dillon carbide ring sizing die, they were all about 0.025" shorter than they had been when they were new. The combination of low pressure and a slightly tapered chamber to fill had expanded the brass enough that resizing would move a little of the wall brass permanently to the rear at each resizing, taking about half a thousandth off their length each time.
Your 45 Colt may or may not shorten like that. Your chamber walls are straighter than the 45 Auto has, so unless they are on the wide side, I would expect to see less of that. Because resizing extrudes the case longer, to monitor the effect you must always measure the cases at the same point in the load cycle to detect a permanent change. Always measure right after resizing to detect a change that might affect your crimp dies setting. Compare the last as-resized measurement to the current as-resized measurement to learn of a permanent change. You could also compare as-fired brass from one load cycle to as-refired brass from the next load cycle, but that won't tell you if you need to adjust your crimping.
The reason high power rifle cartridges need trimming is their peak pressure is high enough to stick the brass body to the chamber while the head is pushed back to the breech face, stretching the brass at the pressure ring where it transitions from thin to thick near the head. One reason this happens is the speed and magnitude with which the pressure builds and the other is that a bottleneck rifle case has the shoulder pushed against the chamber, helping to resist having the whole case move back before the pressure reaches the sticking point. Straight wall cases don't have that, so they need higher pressure to stick to the chamber to stretch than bottleneck cases do. The transition pressure, where sticking begins for bottleneck cases is usually around 30,000 psi peak. For straight-wall cases, it is often closer to 40,000 psi. Your 45 Colt is not at high enough pressure to grow brass.
In a case that has stretched where the pressure ring winds up, the increase in length occurs during resizing as the body is extruded narrower, pushing the brass at the front of the case forward. In a case that has not stretched at the pressure ring location, the whole case has backed up to the breech of the chamber, bringing the mouth with it. When that occurs, the whole case expands outward to seal the chamber against rearward gas leaks, and the brass to provide that extra width is acquired the opposite way from how the sizing die squeezes a case longer; it is done by pulling the case shorter. So, when you measure a fired low-pressure case from a chamber that had any wiggle room when you chambered the cartridge, it will be shorter than it was when you loaded it. When you resize it, the sizing process is merely putting the brass back in place...assuming it can.
I once ran some bulk-purchased 45 Auto brass through 50 light target shooting reload cycles. Just under 1/3 were left by then, the rest having split or been inadvertently sacrificed to the range gods. After resizing straight-sided with a Dillon carbide ring sizing die, they were all about 0.025" shorter than they had been when they were new. The combination of low pressure and a slightly tapered chamber to fill had expanded the brass enough that resizing would move a little of the wall brass permanently to the rear at each resizing, taking about half a thousandth off their length each time.
Your 45 Colt may or may not shorten like that. Your chamber walls are straighter than the 45 Auto has, so unless they are on the wide side, I would expect to see less of that. Because resizing extrudes the case longer, to monitor the effect you must always measure the cases at the same point in the load cycle to detect a permanent change. Always measure right after resizing to detect a change that might affect your crimp dies setting. Compare the last as-resized measurement to the current as-resized measurement to learn of a permanent change. You could also compare as-fired brass from one load cycle to as-refired brass from the next load cycle, but that won't tell you if you need to adjust your crimping.
I too trim one time to get more consistent crimps. I also segregate brands that are shorter than the nominal I need for my crimp setting. I don't size new brass, so it gets loaded and fired once before sizing and measuring, possibly trimmed. The trick is deciding on a nominal and what is a tolerable range, because a few thousandths +- is not important. The sensible nominal is a number that avoids trimming once-fired brass.
My S&W 19-4 will not chamber full length .357, so I have a special trim length for it, .010 shorter nominal (1.265).
I suppose ammo would shoot okay without all that, but my reloading is a craft that I like to do with some precision, short of being obsessive about it.
My S&W 19-4 will not chamber full length .357, so I have a special trim length for it, .010 shorter nominal (1.265).
I suppose ammo would shoot okay without all that, but my reloading is a craft that I like to do with some precision, short of being obsessive about it.
Pathfinder45
New member
This:
As a long-time 45 Colt reloader, I say, always resize new brass and always trim new brass as well as any once-fired or new-to-you brass. After that, I don't trim it again. This may not apply to more modern revolver calibers that have always been more standardized, like the 357 magnum. But with the 45 Colt, I've seen jacketed .451" bullets fall right into and out of brand-new un-sized brass, since the cartridge was designed for .454-.456" lead bullets in the early 1870's.I always trim mine the first time to get everything the same length and consistant. Sometimes theres a huge difference in lengths.
New brass can easily be tested in a sampling for how or if it will accept a bullet without sizing the brass. In my case I have several revolver calibers for which the only new brass I ever bought was Starline and one cartridge in Winchester, which generally load the same for me with a little variation in head thickness and then fit on a specific brand/thickness of shell holder. Not true for all of their cartridges, but I learned to watch out for Remington (R.P.) as having thin case walls and then not sizing down as tight an inside diameter as other brands. Bullets could even be pushed in or drop in freely depending on diameter. So the only Remington I use is nickel plated for my cowboy gun belts, and those have sized normally. I use Winchester and Starline and only an occasional batch of Federal.
After all that, my point is that my context for not sizing new brass is Starline, because the way it galls on the expander after sizing is unacceptable, and it works well without sizing. The expander is RCBS Cowboy for lead bullet sizes. The expander for XTPs might be okay, but the sizer in that die set is smaller, potentially producing the same problem of galling. Tricks to prevent galling like car wash baths were not sufficient.
But we have plowed this row before.
After all that, my point is that my context for not sizing new brass is Starline, because the way it galls on the expander after sizing is unacceptable, and it works well without sizing. The expander is RCBS Cowboy for lead bullet sizes. The expander for XTPs might be okay, but the sizer in that die set is smaller, potentially producing the same problem of galling. Tricks to prevent galling like car wash baths were not sufficient.
But we have plowed this row before.