[Northwest Cajun]

Hi All,
I was working up some loads for my Bushy AR .223 with 55gt V-Max, 25.3gr of Varget CCI 400Primers and Mixed year LC brass.
The 100 groups were nice and small but in two different places. I shot 10 rounds at a time, about 1/2 were in a nice 1" group dead on and the rest were is a nice 1" group 3 " up and right. The scope is a Bushnell 10X mil dot in a Armalite one piece QR mount for a flat top.
Some of the other loads I tried had the same pattern but the shots were strung between the center and the upper right corner of the target.
(My targets are made by tracing the outline and center hole of a Compact Disk)
Really cheap :rolleyes: but effective!
Out of the 50 or so rounds I shot today, only 1 did not feed properly when I pulled out the round I saw that the bullet had been pushed back into the case, Could this be why I'm getting such irratic placement of groups?

I make my loads in a Dillon AT500 with RCBS Small base dies and a Lee Factory crimp die. My powder measure is an RCBS that I charge manually.
Any help would be greatly appreicated.

Cajun

[P95Carry]

Bullet pushed in .......... hmmm ...... odd when you are using the factory crimp die .. I place a lot of faith in that. Maybe crimp a tad too weak .........but anyways ... if you did suffer some OAL vaiations then lead would of course change from round to round perhaps.

Wonder if feed ramp profiles are smooth enough ... I had to work on my L1A1 to ease feeding..... cos bullets were gettin slight nose deformation .. had that allowed bullet to seat lower then perhaps I'd have got your prob.

Not really an answer per se .. just thinkin out loud!:)

[Northwest Cajun]

Would mixed year Lake City brass trow off groups that much?
If my scanner was working I'd post my target but it just went T U.:banghead:

Cajun

[dan newberry]

You might want to weight those LC cases. I've got some that are actually in the 94 grain weight range, and others which are well below 90 grains.

That could be doing it, yes...

Dan

[Khornet]

is often a sign of scope looseness, so check your mounts and scope. Hard to imagine a loading inconsistency that is so consistent.

Other possibilities include barrel stress-relief, so that barrel moves as it heats up, or something bearing on barrel pushing or pulling it as it heats up.

I'll bet you have good ammo which consistently shoots into a nice group, but it's being launched in 2 different directions.

[Poodleshooter]

Scope loose as Khornet mentioned, or possibly a shift in your cheek weld. I've had that do weird things to my groups using short eye relief, high power scopes.

[hps1]

First let me say I have absolutely no experience with the mouse gun (but fixin to learn as my grandson just got one and asked for some coaching):D

Have loaded a lot of larger caliber ammo and have to agree w/Khornet that I doubt the case weight would cause a 3" jump in group and Poodleshooter made good point in variation in cheek pressure. Have seen different "spot weld" cause two entirely different groups because the eye is not centered in your scope. I suspect this would be especially easy to do with the AR since the scope is mounted rather high to begin with. (Or do you get a good solid cheek pressure with the flattop???)

Another question comes to mind, since you had one bullet push back....how full (of powder) is your case? Bullet jump can have quite an effect on POI, therefore, if some of your bullets were seated long(er), as you originally seated them, and the rest were being pushed back exactly the same amount (until base of bullet contacted powder), it would seem that you would have two completely different loads (both in bullet jump and "case capacity" ) Just a thought. I know this can be a pain with an AR, but,I'd make it a point to single load when checking groups.

By the way, for some excellent targets you can download and print check out:

http://www.uspalma.com/Targets/targets.htm

Let us know what you find out.

Regards,
hps

[larryw]

Something's loose.

I had that happen when working up some 223 loads on a bolt gun: two very nice groups 2" apart when there should'a only been one. Turns out one of the action screws was loose and the action would bounce back and forth in the stock every shot. Quick turn with an allen wrench and things were fine.

Everytime I've had a scope work loose, the shots were all over the place, not in groups, so I'm guessing that's not the problem. But then again, 3" is a bunch off, so maybe it is optics (how's that for definitive? :) ).

Also, some semi rifles throw the first shot (closing bolt by of recoil vs. spring can make a difference). Try wiggling the bolt handle when you load from a fresh mag to make sure the bolt is fully seated.

[Northwest Cajun]

Thanks everyone for the comments. My next time out I'll make sure everything is tight. ( including the crimp)
HPS1, I'm using Varget and H4895. In both, the powder is at the base of the neck. I wouldnt call it compressed but there is no free space.

Cajun