question about .223 case length and loading for ar's.

[brian24]

1. I'm getting oal of 1.752 - 1.765 on my once fired prvi and winchester brass (.223). Max oal length says 1.760. Will the shorter brass have different accuracy or shoot different than than the 1.760 brass. Also will the brass that is at 1.761 and 1.762 really need to be trimmed, or can I just shoot another round out of them and trim them next time? So far I'm planning on serperating my loads by OAL, 1.755 and 1.760 +/- .0001, do I need too?

2. I'm loading for a r700 (bolt gun) and a long range AR (semi-auto w/ 77 hpbt). I'm worried that the loads for the AR are going to need to be crimped w/ a cannelure because the higher worked up loads are compressed. Do you guys that are loading compressed loads and for an semi-auto use bullets w/ a cannelure? I'm using varget and starting w/ 22.7 or 23 gr. and going up to 25.0 gr, bullets are 55/60 gr v-max's and 77 gr smk's and nosler cc.

thanks
Brian

[perpetual otter]

I'd like to know too

[Bug Splat]

1. I'm getting oal of 1.752 - 1.765 on my once fired prvi and winchester brass (.223). Max oal length says 1.760. Will the shorter brass have different accuracy or shoot different than than the 1.760 brass. Also will the brass that is at 1.761 and 1.762 really need to be trimmed, or can I just shoot another round out of them and trim them next time? So far I'm planning on serperating my loads by OAL, 1.755 and 1.760 +/- .0001, do I need too?

That little difference in OAL probably wont make a noticeable difference for most shooters. That being said consistency is the key to accuracy. The more consistent you are with your loads, rifle, rest, temperature (ambient and barrel) the more accurate you and your equipment will be. Removing inconsistent factors eliminates the possibility of that your inaccuracy is coming from that one thing.

Trimming brass for a bolt action is something some do and others don't. I like to let my brass grow and fit my chamber like a glove. Once the brass grows far enough its going to stop at the lands. That is my consistency. Others will trim to a length they like, that is their consistency. All ammo loaded with the intent of using in a semi-auto should be trimmer and full length sized. Semi-autos are built to function with factory spec ammo. You can sometimes get away from this with some rifles but you are at a much higher risk for jams or malfunctions.

2. I'm loading for a r700 (bolt gun) and a long range AR (semi-auto w/ 77 hpbt). I'm worried that the loads for the AR are going to need to be crimped w/ a cannelure because the higher worked up loads are compressed. Do you guys that are loading compressed loads and for an semi-auto use bullets w/ a cannelure? I'm using varget and starting w/ 22.7 or 23 gr. and going up to 25.0 gr, bullets are 55/60 gr v-max's and 77 gr smk's and nosler cc.

thanks
Brian

I don't like to crimp my target loads. Range plunkers sure, but again for consistency I don't like my target rounds to have to overcome an inconsistent crimp because its just one more factor to add while troubleshooting accuracy. Always stick to your load manuals and consult your powder and bullet manufacturer for what they recommend as your min and max load. I tested a number of compressed load using varget and I actually got worse results. Faster is not always better. I found better accuracy closer to the min charge weights. Start at your base charges for each bullet weight and type and work your way up till you find the group you are happy with.

One word of advice, stick to one bullet when you are finding your target load. You could spend a life time and dozens of barrels trying to find the best group. Pick one bullet like the SMK and find out how well it can shoot. You could walk away on the first range day and be stoked with a load. Be happy and stick with that load for the rest of your barrels life. If the SMK did not shoot to your expectations then by all means try a new bullet. I've known too many guys who bought half a dozen bullet types and ended up sticking with the first one they tried. now they have boxes of bullets they will never shoot.

...

[brian24]

Thanks bug. Do you ever have any problems with bullet moving in a semi-auto?

[Jonathan Doe]

The Sierra manual shows 2 different loading informations for AR and bolt guns.

[Gunsrruss]

Sizing

I full length size everything. It's easier for me. Sometimes I need to use my bolt brass in an automatic during a match ( very rare ), but I want to not have any problems because I'm switching guns. So I full length everything. I will reload autos only 6 times on the .223 and 4 on the .308. I do this because I compete and can't have a failure.

You need to keep that brass .005 under Max 1.755 A little less is fine also. You let it get into the lans and grooves and your screwed

[brian24]

You need to keep that brass .005 under Max 1.755 A little less is fine also.

My Lyman manual says that 1.760 is max, so I shouldn' t let'm get too 1.760?

[bohoki]

the theory is that the chamber is a certain lenght and there is a particular size that a case would be to blow up your gun

if it is slightly too long it will not go full into battery and wont shut no matter how much you whack the assist but that one case that is too long but just right when you whack it closed it will close crimping the bullet really tight with the full force of the chamber applied to the crimp as well and could cause the chamber pressure to really get dangerously high especially if they are loaded hot (unsafe reloaders often want to push the limit)

so i make sure my brass is 1.755 or less and well debured

[Red Dog]

I shoot an AR15 and a Remmington 700 that I reload for.

1. I'm getting oal of 1.752 - 1.765 on my once fired prvi and winchester brass (.223). Max oal length says 1.760. Will the shorter brass have different accuracy or shoot different than than the 1.760 brass. Also will the brass that is at 1.761 and 1.762 really need to be trimmed, or can I just shoot another round out of them and trim them next time? So far I'm planning on serperating my loads by OAL, 1.755 and 1.760 +/- .0001, do I need too?
I wouldn't let it go any longer than that. I trim after it gets to 1.76. I don't separate my lengths either. I just keep them between 1.75 and 1.76 and call it good.

2. I'm loading for a r700 (bolt gun) and a long range AR (semi-auto w/ 77 hpbt). I'm worried that the loads for the AR are going to need to be crimped w/ a cannelure because the higher worked up loads are compressed. Do you guys that are loading compressed loads and for an semi-auto use bullets w/ a cannelure? I'm using varget and starting w/ 22.7 or 23 gr. and going up to 25.0 gr, bullets are 55/60 gr v-max's and 77 gr smk's and nosler cc.
I don't crimp any loads for my .223s I thought I needed to untill a bunch of guys said I didn't. If you do decide to crimp, Make sure that all of your brass is the exact same length or you will have dented cases.

If I was loading ammunition that I was going to be shooting in a match, I would trim my cases to the same length. You must be consistant with all of your loads to be the most accurate.

thanks
Brian

[Bug Splat]

Thanks bug. Do you ever have any problems with bullet moving in a semi-auto?

I've never noticed. I've shot one of my AR's (16" 1-9 twist) in bench rest matches a number of times and came out with 1/4" groups at 100 yards and I never crimped. If the bullet did move forward it never hurt my accuracy. My AR liked 40gr V-max and 69gr SMK. Hell of a big spread right. It shot "ok" with bullets in between but it really liked the light bullets or the heavy it it just despised 55gr bullet of any brand. Could not group under 1moa with any 55gr bullet. This just goes to show that barrels have a taste all their own and you really don't know what they like until you try it.

[Nessal]

My personal experience is that I crimp for my AR but not for my Remington 700 in .308. When I shoot my bolt gun, I hand load every round. I run a recipe pretty close to yours' for .223 though. I run a 75gr HPBT with 21gr of varget. I trim ALL my cases to 1.750 exactly and separate them by weight after. I also weigh the bullets and separate by weight. I crimp all of the .223 that goes through my AR. The bullets don't have cannelures but the Lee Factory crimp does a great job at it. This gave me very good consistency.