for you ar guys?
- Thread starter TrxR
- Start date
+1. I'm happy at 0.002-0.004 with my range brass pick-ups. I'm typically using the nosler 77s; and save Berger OTMs or Sierra's for the carefully prepped match brass. I find noslers like a slower velocity, but your mileage may vary.
-Mac
1) Some folks say you don't need to crimp with a semi rifle....
2) Different strokes for different folks...I would never not crimp when loading for my AR's...
3) Buy a Lee Factory Crimp die and don't look back....
4) It's easy to crimp a little or a lot.
5) My $.02...YMMV.
2) Different strokes for different folks...I would never not crimp when loading for my AR's...
3) Buy a Lee Factory Crimp die and don't look back....
4) It's easy to crimp a little or a lot.
5) My $.02...YMMV.
jepp2
Gold $$ Contributor
I typically run just around 0.001". And I fire a lot of rounds through AR's each year.
But there is a very easy way to check if you have enough neck tension. When you are loading your magazine, measure the OAL of the next to last bullet loaded. Load and fire the next bullet. Eject the round in the chamber (this will be the round you measured the OAL on) and measure again. You can see if the feed ramps are shoving the bullet into the case, or the sudden stop is pulling the bullet from the case. I normally see the OAL increase by about 2-3 thousandths during the chambering from a round being fired.
But there is a very easy way to check if you have enough neck tension. When you are loading your magazine, measure the OAL of the next to last bullet loaded. Load and fire the next bullet. Eject the round in the chamber (this will be the round you measured the OAL on) and measure again. You can see if the feed ramps are shoving the bullet into the case, or the sudden stop is pulling the bullet from the case. I normally see the OAL increase by about 2-3 thousandths during the chambering from a round being fired.
nmkid
Gold $$ Contributor
Just this past year is the first time I ever loaded for an AR. I too, was concerned about crimping. After asking in several forums about crimping/no crimping I found the general consensus is...No need to crimp! I use about .002 to.003 and haven't encountered any problems.
I loaded for my M1As for years and I never crimped a bullet. Never had an issue with bullet migration neither. Sierra even advises NOT to use the Lee die on their un cannelured bullets.
To see if you need to crimp, load a couple dummy rounds and let the bolt slam them into the chamber full force. Then measure them again to see if the bullet moved. I usually have a .002" interference fit and then lightly crimp (just enough to feel it). My AR isn't made for precision shooting but will average under 1.5 MOA at 100 or 200 yards. Just a cheap Palmetto AR with a 5.56 NATO chamber and the barrel is not floated. Good enough for social work if needed.
Many reloaders use a Lyman type "M" expander with .003 bullet grip for their AR15 rifles. And if the cases are bumped on to the .226 section of the expander it greatly aids in straight inline seating and reduced runout. And my RCBS AR Series .223/5.56 dies have a taper crimp die for streamlining the case mouth and a slight crimp.
I'm glad I'm not the only one who has noticed when standing on their hind legs the rifle tends move around for some reason.
MikeMcCasland
Team Texas F-T/R
.002 here, and I don't crimp on my AR15s or my .260 on an AR10. I don't know a single AR shooter that does either (those that shoot for accuracy anyway).
I have experimented with a Lee Factory Crimp Die (definitely the easiest kind of crimp die to get setup). That said, I didn't see any accuracy improvements, and figured it wasn't worth the extra step. I did slightly deform a few bullets when setting it up and testing.
In general though, crimping really isn't required unless you're having setback issues, or you intend to be rolling into a combat zone.
I have experimented with a Lee Factory Crimp Die (definitely the easiest kind of crimp die to get setup). That said, I didn't see any accuracy improvements, and figured it wasn't worth the extra step. I did slightly deform a few bullets when setting it up and testing.
In general though, crimping really isn't required unless you're having setback issues, or you intend to be rolling into a combat zone.
MikeMcCasland
Team Texas F-T/R
Just saw this question.
For once fired military brass, I've been using a lee decapping die; it's much more stout than your standard decapping stem. You won't have any problems knocking out primers like you would with a standard decaping rod on a crimped primer. If I try decapping on my Redding FL die it'll pierce a primer and take the decapping pin with the spent primer every 10-15 rounds. I'm normally not a huge fan of Lee gear, but their decapper works quite well.
As for the swaging, I don't think you can do much better than a Dillon super swage. They're ~$100, and it's the fastest/easiest swager that I'm aware of. You'll want to stick to the same headstamp (all Lake City for instance; you don't have to sort by year), but otherwise set it up and start pressing them out. You could probably swage ~500-600 rounds an hour with a few breaks included. I'll do a batch of 1000 cases at a time, and box the swager up until I'm ready for a new batch. I believe the kit comes with both large and small primer swaging rods, as well as a adapter for 45ACP cases.
MikeMcCasland
Team Texas F-T/R
If you're near Round Rock, Texas happy to let you borrow mine.
That said, the swager is adjustable so I don't see how it's possible that it won't swage it deep enough. You can see on the picture below that the brass case sits on a locator rod; the depth of the rod is adjustable via the pictured nut. The rod is flat on the end that goes into the case, and it basically sits flush against the flash hole on the inside of the case. This dictates how much you're swaging. The actual swager is non adjustable, and is connected to the lever; it comes through the handle side of the unit.
What your'e adjusting is how far back that case is going to sit when the swager gets pressed down/handle gets pulled.
If the swager is setup for WCC brass and you try to run LC or IVI, it's possible it needs to be reconfigured for you IVI brass; I've actually never needed to reconfigure mine. That said, once you've configured it for your type of headstamp, you can crank them out.
It's hard to imagine a case that it wouldn't swage, as the primer pocket would be out of spec, no?
Here's a video to help you see how it works:
That said, the swager is adjustable so I don't see how it's possible that it won't swage it deep enough. You can see on the picture below that the brass case sits on a locator rod; the depth of the rod is adjustable via the pictured nut. The rod is flat on the end that goes into the case, and it basically sits flush against the flash hole on the inside of the case. This dictates how much you're swaging. The actual swager is non adjustable, and is connected to the lever; it comes through the handle side of the unit.
What your'e adjusting is how far back that case is going to sit when the swager gets pressed down/handle gets pulled.
If the swager is setup for WCC brass and you try to run LC or IVI, it's possible it needs to be reconfigured for you IVI brass; I've actually never needed to reconfigure mine. That said, once you've configured it for your type of headstamp, you can crank them out.
It's hard to imagine a case that it wouldn't swage, as the primer pocket would be out of spec, no?
Here's a video to help you see how it works:
MikeMcCasland
Team Texas F-T/R
I can't say that I have; I pretty much only shoot Lake City out of my ARs.
I just can't see how IVI would be manufactured in such a way that it wouldn't swage it deep enough. If that were the case, the primer pocket would have to be well outside of spec to begin with, and you'd be seating your primers so deep the firing pin wouldn't make contact.
Secondly, when you're swaging, it doesn't have to run up in the full length of the primer pocket; you're just expanding the very base of the primer pocket. The crimp itself is only applied to the base of the case head/primer pocket area; it's not applying any additional pressure further in the pocket towards the flash hole.
Even if that weren't the case, the Dillon can even be setup to "over swage" if configured incorrectly; it's possible to (mis)configure the tool to where it actually shoves the primer pocket/flash hole area forward, into the case.
If you google ' "ivi" brass Dillon swage ' it will show you a few posts of people using the tool sucessfully on IVI. Unfortunately though, with it being Canadian military brass, not as many folks online appear to be using it.
Lastly, you can always cut or chamfer the crimp out (again, it's just at the base of the case head); It's just WAY more work. My hands ache thinking about it.
Maybe you'll get lucky and another AS member can chime in.
Good Luck!
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