LOA"..how critical ?
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ImjinScout
Member
I am going to assume you are talking about OAL (overall length) or as some use COAL (case overall length). Yes .010 can be critical depending how you are loading. Shorter than recommended and higher charge weight can cause over pressure rounds. Now a few thousands of a inch say +/- .003 not much of an issue. Most press's can be held to that and even tighter. If yours vary by .010 something is not right.
Shooter Magaven
Member
That would be .020 total variance.
Is this happening after seating the bullet, or after the crimp...or what? If so, either way something seams loose.
I assume you are seating and crimping in the same stage.
Is this happening after seating the bullet, or after the crimp...or what? If so, either way something seams loose.
I assume you are seating and crimping in the same stage.
fredj338
Member
That amount, depends on the bullet & load. If you are pushing max, then everything matters. If you are running midrange & below, nothing really starts happening until you shorten up 0.030" or more. Look at 0.010" on your calipers, it isn't much, isn't going to affect pressures much, regardless of the load, unless you are already at max with a high pressure, small volume rd like 9mm or 40.
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Running a 5 stage Lee reloader. Setting bullet depth is the area l am concerned with. Yes, l have a separate crimping die, but that does not seem to enter the equation. It is the bullet seating die that seems hyper sensitive to the reloader stroke.
It probably is me...not following thru the full stroke of the arm....although l am conscientious of that issue.
I find l am measuring each cartridge with OAL to be hovering around 1.50 but running between 1.45 to 1.55.
( one is 1.45... The very next may be 1.55.) Then a small % will be at 1.60 or more...YIKES !! These few (9-10 out of 100) l reinsert in the seating die. They settle down to 1.50 as they should.
I really want to eliminate all the extra handling of my reloads. Rereading this report, l am beginning to see l may be the problem....
My main issue is accuracy as it pertains to this OAL, pressure variation.
Note: l am running LSWCs over light powder loads.
It probably is me...not following thru the full stroke of the arm....although l am conscientious of that issue.
I find l am measuring each cartridge with OAL to be hovering around 1.50 but running between 1.45 to 1.55.
( one is 1.45... The very next may be 1.55.) Then a small % will be at 1.60 or more...YIKES !! These few (9-10 out of 100) l reinsert in the seating die. They settle down to 1.50 as they should.
I really want to eliminate all the extra handling of my reloads. Rereading this report, l am beginning to see l may be the problem....
My main issue is accuracy as it pertains to this OAL, pressure variation.
Note: l am running LSWCs over light powder loads.
David R
Member
I used one of those presses. I had the same results. Switched to another major brand progressive press many years ago.
David
David
Shooter Magaven
Member
Sounds like your bullet tip shape doesn't like your seating die. I had this issue with non-match rifle bullets. The cup of the seater does not match your ogive/tip shape giving you a .005 difference in each load. Then your measuring the COL with calipers from base to tip of bullet and the seater is measuring base to ogive so another .005.
Not critical to me unless your loading match ammo. In which case I'd get a single stage press and competition seating dies.
Btw. I havn't measured a 38spl COL in a while. What i do for accuracy loads is measure the brass and trim to a uniform length then seat the bullet to the crimp groove/canelure. That is more critical in a revolver then the measurement to the very tip of the bullet.
good luck
Not critical to me unless your loading match ammo. In which case I'd get a single stage press and competition seating dies.
Btw. I havn't measured a 38spl COL in a while. What i do for accuracy loads is measure the brass and trim to a uniform length then seat the bullet to the crimp groove/canelure. That is more critical in a revolver then the measurement to the very tip of the bullet.
good luck
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fredj338
Member
Mixed brass & bullet nose variation can easily account for oal variation of 0.010". Come on guys, that is a sheet of paper. Unless you are wedged I to the rifling, it isn't going to matter.again, nothing really starts to happen until you get 0.030" & deeper. Easily seen if you run tests over the chrono.
ArchAngelCD
Moderator, SWCA Member, Absent Comrade
The OAL for the .38 Special doesn't really matter since you are supposed to crimp into the manufacturers supplied crimp groove. The 45 Auto is another case. In reality a slight variation in OAL isn't all that bad. What are the numbers for the 45 Auto ammo?
fredj338
Member
Even in 45acp, not an issue. If you were loading a max charge of powder & seated the bullet 0.010" deeper, it might, might put you into slightly +p zone, maybe. Large volume/low pressure rds like 38sp & 45acp are pretty forgiving.
David R
Member
In a 38 the crimp groove decides OAL. In a 45 Chamber dimensions decide OAL for best functioning and accuracy.
I am not concerned about a few thousandths for pressure unless its a 9mm.
David
I am not concerned about a few thousandths for pressure unless its a 9mm.
David
Are you loading cast bullets with the waxy bullet lube? If so some of the lube may be building up in the seating die, and causing you to progressively seat the bullet deeper the more you load. Keep the die clean.
Reloading 38 spc...reloading ammo cartridge variable LOA 1.40-1.60
This OAL will work with the 110 to 158gr JHP bullets if you are
using a crimp and pay attention to where the cannelure and case meet.
You can "Work" with the length of a case and how much a bullet sticks out in your pistol or revolver to get the best accuracy or one that loads easy and does not hang up.
Just because a bullet has a "Can" on it, does not mean you have to use that OAL, if shooting light target loads.
However this longer OAL will generally not work with the 148gr wc bullet........mostly if shot out of a model 52.
Good loading.
This OAL will work with the 110 to 158gr JHP bullets if you are
using a crimp and pay attention to where the cannelure and case meet.
You can "Work" with the length of a case and how much a bullet sticks out in your pistol or revolver to get the best accuracy or one that loads easy and does not hang up.
Just because a bullet has a "Can" on it, does not mean you have to use that OAL, if shooting light target loads.
However this longer OAL will generally not work with the 148gr wc bullet........mostly if shot out of a model 52.
Good loading.
ironhead7544
Member
The progressives will give a bit more variations. Yours is not bad. For standard type loads it will not be a problem pressure wise.
As you have probably noticed, sizing will feel different with some brass. Once you fire all the brass in your gun, it will probably smooth out. With a case that requires more sizing force, it may give a slightly longer cartridge when seating. The bullet tips are often a bit different too.
As you have probably noticed, sizing will feel different with some brass. Once you fire all the brass in your gun, it will probably smooth out. With a case that requires more sizing force, it may give a slightly longer cartridge when seating. The bullet tips are often a bit different too.
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