Trimming rifle brass.

[snarlingdog]

I have been under the impression that if you do a full resize on rifle brass you should trim it. I watched a guy on YouTube reload 308 and he didn't trim at all. What do you guys do?

And I have always had issues with my rifle reloads not loading easily the last 1/4" even though the sizing die is hitting the shell plate.

I guess maybe I need a refresher on rifle reloading haha

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[oremike]

Dial calipers are you friend, if they are too long trim them. If they are with in spec then you don't need to trim. And yes you do need to resize first.

 

[RVTECH]

All bottleneck rifle brass needs to be trimmed, or checked for proper length, but this is typically done during trimming.

 

[snarlingdog]

I understand that lol

 

[snarlingdog]

I usually check every other after sizing if there is any over spec ill trim my cases.

 

[slacktide]

What caliber and rifle are we talking about? Belted magnum or no? Bolt gun or other?

After resizing you should certainly measure length. If you are within spec you don't have to trim, but I do as I want zero variation from one firing to the next. But if you are having trouble with the load not chambering easily could have issues elsewhere. How does resized brass (not a loaded round) chamber - easy or tough?

A couple things to check:
Even with the shell holder hitting the die it may not be enough to size it fully. Try turning it in a little more.

You may be in need of a small base sizing die - some chambers are cut small but this is usually an issue autoloaders have to deal with. A small base die will size past SAMMI specs for easy loading. (I doubt this is the problem.)

Try sizing a couple with the stem and expander ball removed. This will help determine if the stem is bent or the neck is too large (or too thick) for your chamber. Measure several places on the brass before and after sizing.

 

[Member 5605]

If the brass needs trimming, do so.

If you trim to 2.005" and max length is 2.015" after one firing your brass is 2.010"... no need to trim.

Cept, I trim .308 to 2.000" because I can.

 

[Caveman Jim]

After resizing .223/5.56 I not only measure and trim but if they are under speck (1.445") then I sort HS & throw them in a container marked 300BLK Food.
Every case gets a trip into the chamber checker before and after loading, I take no chances.

 

[snarlingdog]

What caliber and rifle are we talking about? Belted magnum or no? Bolt gun or other?

After resizing you should certainly measure length. If you are within spec you don't have to trim, but I do as I want zero variation from one firing to the next. But if you are having trouble with the load not chambering easily could have issues elsewhere. How does resized brass (not a loaded round) chamber - easy or tough?

A couple things to check:
Even with the shell holder hitting the die it may not be enough to size it fully. Try turning it in a little more.

You may be in need of a small base sizing die - some chambers are cut small but this is usually an issue autoloaders have to deal with. A small base die will size past SAMMI specs for easy loading. (I doubt this is the problem.)

Try sizing a couple with the stem and expander ball removed. This will help determine if the stem is bent or the neck is too large (or too thick) for your chamber. Measure several places on the brass before and after sizing.

This is for both my 7mag and 308. I'm not new to reload just new to rifle reloading. And it's all for a bolt gun.

I'll have to size some brass and see how it is with out a bullet on it to see if that is my issue. Thanks for that idea

 

[eightyeight mag]

I have to trim my 308 every couple of firings but the 300 wsm i shoot rarely needs trimming.

 

[slacktide]

Okay now we are getting somewhere and now my wild guess is that you may be seating too long. Maybe make up some dummies and seat deeper by 0.010" at a time.

If it's a Rem or Win or other that you can take the bolt apart and get rid of the innards you can gain a lot of ground with just the bolt and sized brass and dummy rounds.

 

[snarlingdog]

Ok I can give that a go.

 

[ma96782]

For me with rifle brass (bottleneck brass)......if it's too long....it needs a trim.

Now a days though there is a thing called an X die. The MFN says that you trim once and use their die and no more trimming needed. Sorry, I can't say if it actually works.

Aloha, Mark

 

[v0lcom13sn0w]

i trim for anything larger than 5.56 after its too long on my no go gauge.

i trim 5.56 to spec once and dont really worry about it after.

 

[808hondacrguy]

My 556 and 308 both had issues cambering the last little bit, and my rifle would not go into battery. I searched Youtube, and found a few videos that said to add another 1/2 turn to the resizing die,, and it worked for me. I have no issues anymore. YMMV.

 

[ma96782]

OK, I use to buy 1x fired 7.62 x51 mm Nato brass from the recycle place. They probably got it from the base. Back then, M60s were what most of the ammo was shot out of.

Anyway, the brass was difficult to re-size. I believe that the M60's chambers were "generous." Hey, it's a machine gun.

FF today.....the surplus LC brass is probably coming from a M240.

Anyway, I still use a F/L re-sizer and got into the habit of using a gauge to test my re-sized brass.

STORY:

My reloaded ammo fit my M1a easily. But, when I tried the same ammo in my bolt action Rem 700....well, it didn't chamber. That batch of ammo got regulated for use only in the M1a. Humm.....but, I don't want that to happen again. So, I screwed down the re-sizing die down a bit more. The new ammo is just passing, in the gauge test. Remember, there is a high and a low cut, to test the re-sized brass to still be acceptable. Now, the ammo would work in both rifles.

Bottom line: chambers vary and a little bit could be all the difference.

And.......cam over while re-sizing. I hope you're doing that...RIGHT?

Aloha, Mark

PS....this is the type of gauge that I use. Though mine is made of old fashion steel.

L.E. WILSON, INC. BRASS CASE GAGES | Brownells

There are many other gauges and ways to accomplish the same goals.

 

[po18guy]

7 Mag and 308? That's odd. Try chambering a resized empty casing. Still tight? You might need what are known as "small base" dies - although those are normally used in auto-loaders which have only a spring and not your hand providing the chambering force.

Again, you might measure an unchambered round (with bullet), then chamber and extract it. Measure again. If it is shorter ( or if it extracts minus the bullet) you are seating the bullets out too far for the amount of leade in your barrel. Simply seat the bullets deeper into the case.

 

[gmerkt]

I use an LE Wilson cartridge headspace gauge to check each sized case for length. The gauge will also tell you if your sizing headspace is correct but this you check after sizing your first case. Not after you've sized, say, 100 pieces.

Case length should not be neglected. Too long and the case mouth can get jammed into the leade of the rifling, causes high pressures. Erratic pressures will cause variations in accuracy. High pressures can be dangerous but you usually won't blow up a rifle over this issue.

If you crimp (I use taper crimp on most rifle cartridges), inconsistent case length will result in inconsistent crimp. And possibly slightly crushed shoulders. This can be a cause of a round not chambering.

I find that .223/5.56 cases grow in length just as much as larger calibers if you don't lube the inside of dry case necks. .223 brass isn't all that thick at the mouth, the drag of the expander ball will stretch the neck if it's dry. Depending on method used to clean the case, sometimes I don't have to lube the inside of the neck. Other times, they are very dry and the drag is excessive.

I usually over-trim .223 brass just a little. In other words, I make it shorter than the suggested minimum. I find this doesn't hurt anything and you don't have to trim as often. We're talking about .002. I don't enjoy trimming any more often than necessary. I usually load .223 about four times, then it gets retired to the recycling can.

You'd be surprised how often cases on factory loaded ammo are over-length before their first firing. And sometimes inconsistent in length. They don't have a line where people sit and gauge each case. They have machines that do most everything and pretty finely tuned, too. But not perfect.

I've examined "remanufactured ammunition" offered for sale at gun shows and some showed no evidence of ever having been trimmed. They just resized and slammed them through their Dillon, no trim, no deburring, no chamfer. Makes for fast work, to be sure.

 

[bentoncity]

For brass used in .308 semi-autos, we shaved .002 off the top of the shell holder in the press. That lets the case get shoved further up into the small base .308 f/l die. That .002 is enough to let the rounds chamber (into semi-autos) without issues after trimming.
[The shell holder sets snug on the bottom of the die.] This method was used because we bought 1000 rnds of once fired Federal brass that, unknown to us, must have come out of a machine gun.

We run every .308 case past the LE Wilson case trimmer with the power head after doing a f/l on unknown brass. Takes about 5 seconds or less per round.
FYI, the 1st time we worked the brass via the f/l small base die, it would chamber in a bolt action but NOT in two different semi-autos that had correct headspace. This was even after trimming .005 UNDER length.

Dan

 

[BrandonQuixote]

Calipers and a chamber checker go a long way