Crimping vs neck tension

[acs75]

I'm interested to hear guys opinion on this. Mostly for AR-15 223 n or 300 blackout.
In my bolt guns in run .003 neck tension to get the best accuracy.
Why don't guys do the same for AR-15? Instead of crimping. My thoughts are crimping wouldn't always give you consistent tension on bullet. Due to slight variation in case length (yes I like everyone has slight variations to many variables imo). Where setting neck tension through expander ball on Forster dies will give you that. I don't like Redding type s bushing dies. Doesn't make sense to set inside diameter by adjusting outside diameter.
For argument sake let's assume everyone trims n turns their necks n anneals.

Let me know. I'm going to start to dial in my ARs. Would like them to be more consistent and stretch them out 300 to 1000 yards with right setup. But mostly MOA at 400 to 600 yards.


Would like to hear from ya.

[hammAR]

I don't crimp any of my rifle rounds............There is lots of info & even more opinions both here & on other web sites. Some say do & some don’t, it seems either side usually has a valid reason for their reason or choice.

Scroll down to "Neck Tension" and read what the experts at Sierra have to say.
LINK

I have total confidence in my non crimped rounds that I shoot...............

[acs75]

I don't crimp any of my rifle rounds............There is lots of info & even more opinions both here & on other web sites. Some say do & some don’t, it seems either side usually has a valid reason for their reason or choice.

Scroll down to "Neck Tension" and read what the experts at Sierra have to say.
LINK

I have total confidence in my non crimped rounds that I shoot...............

I'm more interested in guys that don't crimp. Do you set your neck tension tighter?
Like I do in my bolts at .003. .001 tension without crimp seems really light to me.

Yes I can n have read what "experts" say about it. Read all the forums. But you don't see them talk specifically neck tension.
I just wanted to hear what gas guys thought about it.
Interested in what guys are doing today. What you have tried whether it worked or not.
Other thing is as bolt guys we adjust our seating depths based on chamber length. .020 .030 .060 off lands. With ARs we are limited in magazine lengths. How do you set your seating depths.
All of this makes a Big difference in bolts.
Just looking to pick your brains. What you do or don't n why.

[crbutler]

I crimp anything in auto guns and dangerous game calibers.

Heavy bullet revolver loads are also crimped.

I have seen some substantial set back with .223 ammo in an AR with uncrimped factory ammo.

I always figured if uncle wanted it crimped, it was for a good reason.

However, it does reduce accuracy some in my experience.

[Seismic Sam]

I crimp anything in auto guns and dangerous game calibers.

Heavy bullet revolver loads are also crimped.

I have seen some substantial set back with .223 ammo in an AR with uncrimped factory ammo.

I always figured if uncle wanted it crimped, it was for a good reason.

However, it does reduce accuracy some in my experience.

You are right, Dr. Reloading Breath!! Case and bullet concentricity are primary factors in accuracy, and after you get a loaded round with .001" runout, putting a crimp on top of that is MORE rather than less likely to increase the runout. Unless Forster comes up with a co-ax crimp die to go with their co-ax size die, there isn't much you can do with it.....

[Rip Van Winkle]

From an accuracy standpoint, if you're using uniform brass, there's no advantage to be gained by crimping.

In the match ammo I load for my AR I use between .002" and .003" tension depending on the brand of brass. I wouldn't use less than .002" unless you're shooting a single shot target rifle, and I've seen no advantage of using over .003".

[acs75]

From an accuracy standpoint, if you're using uniform brass, there's no advantage to be gained by crimping.

In the match ammo I load for my AR I use between .002" and .003" tension depending on the brand of brass. I wouldn't use less than .002" unless you're shooting a single shot target rifle, and I've seen no advantage of using over .003".

That's what I figured.
What are you shooting for bullet n powder you using?
How do you dealing with O.A.L with magazine restrictions?
What distance you shooting?
Any info would be appreciated.

I'm just doing load workups on bulk bullets. Basically playing around.
I have Fully prep all the brass as I do fit my bolts. Brass is lake city. I loaded a lot 55gr h335 on Dillion.
Now Just trying to get a feel for precision loading for gas gun. Wasn't sure how it related to bolt action. They seem to be more temperamental then bolt.
At some point I will build another one using match grade parts. Till then see what these will do.
I have 62gr
SS109s also but save them for barrel that can handle the length.
Varget
H322
H335

[OldmanFCSA]

I have 3 AR's that I crimp by light"taper crimping" which isn't as critical for length.
My other 3 AR's use ammo that is not crimped at all, accuracy is the prime directive for those.

My target 50 uses 0.005" for seating, but I use solid brass bore-riders that only have a 0.150" length sealing band. I can hand-pull projectiles if need arises.

[Rip Van Winkle]

My go to match load is 23.5gr of RL15 ignited by a Rem 7.5 BR primer. I'm currently using PSD brass which is comparable to LC (08, 09 & 10). For the short lines (200 - 300 yards) I use a Nosler 77gr CC bullet seated to magazine length. For the long lines (500 - 600 yards) I substitute a Berger 80.5gr Fullbore bullet seated .015" off the lands. The long line loads need to single loaded as they're too long to fit into the magazine.

IMHO, you're wasting your time playing with the seating depth of the two bullets you've listed. Both are jump tolerant, and neither would be considered to be match quality.

[acs75]

My go to match load is 23.5gr of RL15 ignited by a Rem 7.5 BR primer. I'm currently using PSD brass which is comparable to LC (08, 09 & 10). For the short lines (200 - 300 yards) I use a Nosler 77gr CC bullet seated to magazine length. For the long lines (500 - 600 yards) I substitute a Berger 80.5gr Fullbore bullet seated .015" off the lands. The long line loads need to single loaded as they're too long to fit into the magazine.

IMHO, you're wasting your time playing with the seating depth of the two bullets you've listed. Both are jump tolerant, and neither would be considered to be match quality.

I also don't have a barrel to shoot those heavy bullets Yet. So I will dial in these ARs. Then build longer range rifle.

What barrel, lengths n twists are you shooting? Bullets that you see work better in certain combinations of barrel specs?

Rip can you answer these questions for me Thank You

Also what brass are using that you go to two different neck tension ?

[acs75]

Also back to my original question.

Why do guys crimp? Why not set proper neck tension instead? Is there an issue that I'm not seeing? Definitely we know accuracy is better with proper neck tension vs crimp.
Is it because that's the way it's always been done?
If you run .003 neck tension you should have no issues with bullet creep?
If you read most forums relating to reloading for ARs there is always the argument to crimp or not to crimp. But never discussion on neck tension. I assume if they don't crimp they just running standard .001 neck tension. Again seems light.

[crbutler]

You seem to have already decided this for yourself.

Regarding rifles... to me, bolt, semi auto, or double gun, it's your use that determines crimping, not the platform.

Pretty much anything with substantial recoil needs crimping if you are worrying about absolute reliability. As I said, I have seen black hills .223 ammo put the bullet into the case with some non crimped stuff using an AR. I also have some select fire weapons, and anything going in them is crimped. I have done side by side comparisons of crimp or no crimp. Crimping is an extra step, so if you don't need it, don't do it.

As Rip said, some bullets, it doesn't make a difference with. Bulk FMJ .224 bullets show more dispersal than the crimp gives. Also, while I have only seen it in magnum handguns and in my .470 NE, some times a stiff crimp makes the ammo more accurate than without crimping (supposedly it makes for more uniform ignition.)

Prairie dog ammo I let neck tension deal with it.

Deer hunting, since I refuse to bust them at extended range, 1MOA is plenty accurate, and crimped loads with the bullets I use meet that requirement.

African and out of state/country hunting is all crimped. Some very heavily.

3 gun ammo I crimp.

PRS ammo is not.

Essentially, if my uses require absolute reliability, its crimped. I don't shoot high power or benchrest, and while playing the smallest group game can be rewarding in its own right, for my uses sub moa is good enough, and even with crimping I make that standard.

I don't mic each case, and really am not going to spend the money to acquire neck dies for the multitude of cartridges I reload. Unless you are going to neck turn, your statements about neck tension are a bit too inflexible.

I understand you can go down that road if you are looking for the last increment in accuracy, but I can't shoot that well except with a formal bench rest, and since I have tried comparisons without finding too much difference, it's pointless to me to worry about the minute gains in accuracy vs. the proven increase in reliability. When it makes a difference in my hunting or match scores as far as not crimping, I will reevaluate my plan.

[acs75]

Again I'm Not asking whether people should crimp or not. Although I wonder why would you crimp. When you can eliminate a step n have more consistent results by setting neck tension. But I digress.
Yes I made up my mind on bolt. .003 neck tension is perfect. I don't know anyone who crimps bolt action. Again if you do that's fine with me.

If you don't crimp do you change your neck tension on your ARs? To help ensure there isn't any bullet creep? And to be more consistent on poi.

The question/argument isn't whether crimping is good or bad. Or whether it helps or not.
Im just wondering who if anyone use strictly uses neck tension on ARs to achieve their goal?
I understand and agree with everything you are saying. I'm not really looking for advice. I just thought I would ask the question. Who adjusts neck tension in their ARs? Do you have any issues with bullet creep when you use a specific neck tension (.002 .003 .004)?
Yes I am trying squeeze out every last bit of accuracy. Why. Because I Can LOL. I have time n enjoy doing so.
I'm not a hunter n don't shoot comps. I just like to push my abilities n my knowledge.

I appreciate the feedback

[Rip Van Winkle]

There are 2 reasons to crimp, both have to do with quality control. Commercial manufactures crimp their product because they have no control over how their ammunition is handled in shipping and storage. Military ammunition is heavily crimped to insure reliability. It would be disastrous to have ammo which won't reliably feed through the magazine. As noted above, heavy recoiling cartridges need crimping to insure reliability.

The handloader can see an improvement in accuracy using a crimp on a mixed lot of brass. Unless properly annealed, brass work hardens. The more its worked the harder it gets. Brass that's been reloaded multiple times is going to be harder than virgin brass. Manufactures also use different alloys for their brass, Federal brass for example, is notoriously soft.

As a side note, in an effort to insure consistency, most reloading dies overwork brass during the sizing process.

[acs75]

Yep I know all that.
As I stated above. Unless I'm reloading on Dillon for quantity. I fully prep all my brass. Necks turned, primer pockets, flash hole, trim, anneal every other firing. I use a k&m priming tool, coax press with Forster dies. I have my 260 rem die honed to prevent over working. The 300WM n 223 are not because my necks are thin enough I don't have that issue. I have expander balls honed to give me .003 neck tension needed. I measure everything I shoot through my rifle.
I don't like federal brass it's junk.
I only use lapua, nosler in 300WM n LC in ARs.
Again I'm not arguing to crimp or not or it's value to do so.
Neck tension.
But Thank You for your opinions.