.308 COL 2.010 safe to load? or time to trim?

[5RWill]

Bout to go reload as much as i can today and while i have 50 pieces of brass that have only been fired once, i have another 50 that i want to reload that have been fired twice. Majority of the cases are @ 2.010, max length is 2.015 but at just five thousandths shorter than max length would it be unsafe to load and shoot them due to expansion?

Also haven't trimmed since using my .260 brass. Order wise is resize, trim, debur, then load? Or is it trim, debur, resize, and then load?

[dawico]

I resize first and then trim. They can grow some in the resizing die, and it just seems more accurate to size them and then trim.

If the case is under or at max length, then it is ok to shoot.

When you go to trim them, resize them all and trim them all. It takes longer to sort them than just to trim them all.

[Clifford L. Hughes]

Blackops 2:

Wilson makes a gage that measures both head space and case length in one operation, It is accurate. After resizing just drop the case into the gage. On each end of the gage is a step that indicated minimum and maximun length. One end measures the case length; the other end measures shoulder to base length. I trim my cases to be several thousands under minimum so that I don't have to trim as often. I hope that this has helped you.

Semper Fi.

Gunnery sergeant
Clifford L. Hughes
USMC Retired

[Clifford L. Hughes]

Blackops 2:

Wilson makes a gage that measures both head space and case length in one operation, It is accurate. After resizing just drop the case into the gage. On each end of the gage is a step that indicated minimum and maximun length. One end measures the case length; the other end measures shoulder to base length. I trim my cases to be several thousands under minimum so that I don't have to trim as often.

Semper Fi.

Gunnery sergeant
Clifford L. Hughes
USMC Retired

[Clifford L. Hughes]

Blackops 2:

Wilson makes a gage that measures both head space and trim to length in one operation. On each end of the gage is a step that measures minimum/maximum length. On the other end the gage measures Minimum/maximun shoulder to base length. Just drop a sized case into the gage and instantly you have your case analyzed. They even make an adjustable gage that allows you to set up your belted magnum cases to your rifle's chamber.

Semper Fi.

Gunnery sergeant
Clifford L. Hughes
USMC Retired

[Unclenick]

Blackops 2,

The SAAMI chamber drawings specify the chamber neck be a minimum of 2.025" from the breech face, or 0.010" longer than the maximum case case length to that point. So, yes, a maximum is perfectly safe to fire.

The SAAMI case length specification for the .308 Winchester is minimum 1.995", maximum 2.015". Manufacturers of brass don't usually trim as accurately as handloaders do. As a result, manufacturers aim for the middle of that range in order to have some slop available. You don't have to do that. Indeed, many trim cases to the minimum and let them grow to maximum just so they don't have to trim as often. If you crimp, though, it is best to have them all the same.


Clifford Hughes,

When you read how your reply posted, notice there is a little button in the lower right corner that says "Edit". Click on that to make corrections. It will also give you an opportunity to delete your extra posts.

[4runnerman]

Howdy Blackops-- Resize,trim,chamfer,reload.A few more steps in there but,,,
I trim all mine back to 2.00 everytime i shoot. Your overall length is ok at 2.10. Make sure you have neck bumped back far enough before loading. Can lead to one sticky bolt if not. Fired twice i would definetly check the necks. Also it depends on the brand brass you are using too. I shoot Nosler for comp and Win for just practice. Nosler is god brass,does not expand much at all. Win brass i find i need to trim all the time AND bump the necks back everytime.

Let us know how it goes for ya..

[5RWill]

5 and a half hours later i'm back, lol loaded 77 rounds of berger 175gr. Also using nosler brass. On the 40 or so that had been fired twice i measured them twice to reassure, resized and went ahead and primed them, putting them to the side focused on the newer 50 and loaded them all. When i got to the lot that had been fired twice, i started measuring again and while most remained around 2.010, i figured i would trim them. Well i made the stupid mistake of priming them first, which i think has to add at least a couple of thousandths or so on the case? I'm not sure but they were all different lengths just by a couple of thousandths and i trimmed about 4 and realized i was having to adjust the trimmer to each one to take off so many thousandths and try and get them at 2.005. So i got irritated and just ended up loading them. Idk whether i'm lacking common sense or what but between the RCBS trim pro and the lyman trimmer i have which are both just basic trimmers, they irritate me. I load at a friends house who has taught me everything so until i can get my equipment set up i guess ill let him monitor me when i trim. I do know that when i buy my trimmer it will be the wilson with a micrometer, I want to physically adjust and know how many thousandths i'm taking off instead of having to work back and forth and measure. Same goes with the regular dies drives me a little on the edge having to measure every round with the caliper to make sure i'm staying consistent. I did consequently ruin a piece of brass when trying to seat a bullet, i guess i had a little cam in the press that i didn't notice and when i tried to seat the bullet it put a double ring around the neck. I would've ran it back through the resizing die but since it wasn't my stuff i figured i better not incase it got stuck.

I ran a couple of rounds of the twice fired rounds through my bolt action, to see how sticky or how hard the cam of the bolt was and it's pretty tough but i've dealt with worse on my friends 22-250 when we went shooting one time. We'll see how i goes, definitely frustrated a little bout to hit the books again and start reading.

I do wonder though, since the neck is longer on the twice fired rounds would that cause a pressure increase/difference in velocity? Would i see a dramatic difference in accuracy in a sense?

I left the die alone when moving to the twice fired brass which i had seated the newer batch @ 2.805, leaving the die and seating the bullets in the twice fired initially had them @ 2.810 so i adjusted down to 2.805. But essentially that is seating at a different depth right? Because the neck is longer on the twice fired brass the COL would be longer anyway?

Clifford thanks for the recommendation i will definitely give it a look.

Still have so much to learn

[dawico]

The COL is the same no matter how long the case neck is.

When you deburr the cases after trimming, you can cut them shorter by deburring the case too much. Just set the trimmer and go. I don't understand how you can need to readjust it for every case. If you had them primed and the trimmer has a ball that presses into the primer pocket to hold the case (which my old Lyman had), then I guess that could change the lengths. That is very dangerous also, as it could set off a primer.

You really don't need to crimp .308s for a bolt gun. They don't recoil that hard.

[5RWill]

I didn't think i was crimping. Isn't a crimping die needed for crimping? Sorry i've never looked into crimping and don't fully understand it, as i read it wasn't necessary for Bolt rifles. As for the trimming, i suppose the cases were just different in lengths. I had one from the twice fired lot that was below 2.010 and around 2.006. All in all i figured it was best i just load them if they were safe to load, just incase there was something i was missing or doing wrong while trimming.

[dawico]

Your bullet seating die will crimp also, most if not all do. Just make sure the die is not touching the case. Put an empty case in the shell holder and run the ram all the way up, then turn the die in until it makes contact with the case. Then turn the die back out one full turn and lock it down. Then put in a bullet and set the seating die, making sure the ram is all the way up again.

You shouldn't feel the ram cam over hardly at all. From your post earlier when you ruined the case, you were crimping it too much.

[5RWill]

Oh yeah I when I first put the die in I bottomed it out and had no cam on it I initially thought, but it had a tiny pit, so I re adjusted. Thanks for all the help

[Unclenick]

Sounds like you still have some confusion going on. First, always size before trimming. When the brass goes into the sizing die, as it first contacts the sides of the die, that narrows it. Narrowing it also squeezes it out longer. Running into the shoulder of the die shortens it again, but only at the shoulder, not at the neck. At this point the case is as long as it's going to get, which is why you trim only after sizing. An illustration I made is below.

If priming is lengthening your cases, then the primer must be sticking out. That is bad for ignition regularity. In a self-loader that increases the chance of a discharge occurring when it loads (slam fire), but it causes trouble in bolt rifles as well. A high primer isn't making firm contact with the bottom of the primer pocket. When the firing pin strikes it, the primer goes further into the pocket because it wasn't seated fully. This can cause failures to fire or weakened or delayed ignition of several 10's of milliseconds. Those give more time for any small movement of the gun to go off target before the bullet leaves, so it opens groups up. It can also cause more irregular muzzle velocity, which opens groups up at longer ranges.

Primers should be 0.003" to 0.005" below even with the case head. You can learn to feel for this with your finger.

[5RWill]

I'm hoping that the primers weren't sticking out at all. I knew the recommended seating depth was .003-.005, was using a RCBS hand prime, which i'm against but it's not my set up. I would much prefer a ram prime or the RCBS priming station for better consistency. Might have to look over some and see what they look like, although i checked over everyone after priming and feeling the case they seemed fine. I'm guessing the cases just stretched all around the same length just varying a couple of thousandths?

[Unclenick]

I've never noticed priming affecting length, though I suppose if you had a thin enough rim you could bend it back with the shell holder if you pushed on the primer enough. In any event, it's hard for a caliper to repeat to the nearest thousandth on cases. You rotate the case, wobble it into position and you can often get that much disagreement between successive measurements.

As I mentioned, you can feel a high primer with your finger. If you want a simple measuring test, place the tip of a flat blade screwdriver on the case so it bridges across the primer pocket. A narrow (narrower than the primer) strip of typing paper should be able to slide between the blade and the primer.

[5RWill]

Will do, i was wondering how i could test to see if they're seated properly.

[dawico]

I use the back end of my calipers (opposite the head). They have a bar that slides out for internal measurements, and it works good for measuring primer depth.

[mehavey]

...how i could test to see if they're seated properly...

So easy (a caveman could do it)

Put any straightedge across the case base/seated primer.
If you can see a sliver of daylight above the primer, you're good-to-go

[5RWill]

Primers are seated a little out, not to bad, but i'll seat them deeper next time. Shot 10 shots today with the twice fired brass. Surprisingly there was not much bolt stick, it was pretty easy, a lot better than i thought. Here is a 5 shot group i shot, 2 to get warmed up i'm not shooting as much as i used to so i need warm up shots

Should've steadied my breathing more, started off as a semi ragged hole 3 shot group.

[Unclenick]

Shouldn't be any bolt stick. That would be a pressure sign. The only time it happens is when steel is stretching beyond the elastic limit of the brass it surrounds. Not cool.

The force of firing is seating the primers flush after they go off.

The drop in the two low rounds aren't necessarily caused by you. They could be caused by ignition delays due to the high primers. Read this.

[mehavey]

Primers are seated a little out, not to bad, but i'll seat them deeper next time.

Seat primers until they stop.
Don't try to 'tailor' the depth.

If the primer pockets aren't manufactured deep enough to seat primers properly by the "Stop" method, get thee to a primer pocker uniformer ASAP.

[5RWill]

I thought about seating them deeper but it scares me the thought of trying to do it with a loaded round. While the delay of ignition to the primer could be a cause of the first two rounds being low, it also could be that I adjusted my zero stop on my scope likely moving my zero. I had too much play behind my zero stop, so i adjusted it, likely accidently moving my zero down a little. But i could be either or. The rest of the rounds were pretty consistent. Out of the ten i fired.