New rifle not grouping

[White Smoke]

I just got a CZ600A1 in 223 caliber. For the life of me, I can't get it to group under an inch. I have tried several loads that are sub-half inch in other rifles, even a box of match ammo. These were all 55-grain projectiles. The rifle has a 1:7" twist and i have been advised to try a heavier bullet. I now have three ladders loaded up with Reloder 10, Varget and H335 using  69 grain Sierra Tipped MatchKing. Anyone have any other suggestions other than send it back to CZ for a checkup. Several other club members have the same rifle, and everything they shoot is under an inch.

[M1A4ME]

The best shooting loads I've ever made (45 grain and 55 grain) for my M700 varmint special used IMR4198.  I tried a lot of powders in the M700.  IMR4198 won out.  Darn it's expensive these days.  The M700 has a 1 turn in 12" barrel as it was made back when .223's were mostly varmint rifles used for shooting varmints.

I've never tried anything heavier in the AR15's and the twist rates run from the 1 turn in 9" to 1 turn in 7".  I do have a 1 turn in 11" heavy bull barrel on one AR15 and it shoots 45 grain bullets with BLC2 really well (a load that failed to impress me in the M700 almost 40 years ago).

These days my go to powder for 55 grain FMJBT Hornady bullets is BLC2.  They seem to do well in any twist. 

H335 works well, too.  Just not quite there with the BLC2 load.

Tried TAC a few years ago with the 55 grain bullets.  The most accurate load was a grain or more below max.  They worked fine in the carbine and rifle that first summer.  Come winter time and on a 20 F afternoon the rifle short stroked often.  No sense, to me, to load more powder just to shoot bigger groups when the BLC3 and H335 function and shoot good groups.

[Wobbly]

Welcome from Georgia.

Please take a few moments to familiarize yourself with all the sticky posts in the 'New Members' section. Together with the Help Topics in the 'Important Information !' or 'FAQ' sub-section, these include 'how tos' such as 'how to' post pictures on the forum.

[White Smoke]

Thanks for that, but has anyone shot both 55-grain bullets and heavier bullets, like the 69-grain Tipped MatchKings, in the 600A1 or anything with a 1:8 twist. I just want to get an idea if the heavier bullets shoot better than 55's. I'm going to the range on Tuesday. Guess I'll find out for sure then.

[Wobbly]

The best shooting loads I've ever made (45 grain and 55 grain) for my M700 varmint special used IMR4198.  I tried a lot of powders in the M700.  IMR4198 won out. 

This is my experience also.

[M1A4ME]

Guns are funny.  What works/shoots well in mine might not in yours.

Any of the match/heavy bullets with the right powder and right reloading procedures/steps/prep. could shoot nice groups, but not every single one will.  One will usually outshine the rest.  Sometimes you get really lucky and you buy a rifle that has a couple/three loads it shoots really well.  Only sometimes.

They (internet wisdom) the 55 grain FMJ bullets won't shoot the small groups better bullets will.  Even (the claim is) the Hornady 55 grain soft points will shoot better than the Hornady 55 grain FMJBT.

I've also read, for distances under 300 yds. you're better off with a flat based bullet than a boat tail bullet.  Better groups, cheaper to buy. too.

Have you shot any of your friends Sub MOA reloads/ammo through your rifle?  Just to see if their ammo shoots better than yours then you'd have a better idea of what to look at next.  Trip back to CZ?  Or work on doing something different with the reloading steps/procedures?

Does CZ ship a target, or a representation of the target used at the factory to insure the rifle shot/functioned like they used to with pistols?  They usually listed the brand/bullet weight of ammo used at the factory.  That info might be good to know, too.

[bang bang]

I just got a CZ600A1 in 223 caliber. For the life of me, I can't get it to group under an inch. I have tried several loads that are sub-half inch in other rifles, even a box of match ammo. These were all 55-grain projectiles. The rifle has a 1:7" twist and i have been advised to try a heavier bullet. I now have three ladders loaded up with Reloder 10, Varget and H335 using  69 grain Sierra Tipped MatchKing. Anyone have any other suggestions other than send it back to CZ for a checkup. Several other club members have the same rifle, and everything they shoot is under an inch.

welcome

take or leave....and not in any order...my feeling is that its like doctors...."do no harm - first" or use the KISS principle and THEN go down that rabbit hole.  I have no idea on who you are, what you have done, experience, patience, bank account, time and so forth.   so, again, take or leave....

 > are you a good shooter?  Some people leave out the shooter.  when troubleshooting suspect everything and everyone.  Did you try having someone else shoot it?

 > are you keeping a reloading log? 

 > is the rifle scoped?  is the scope any good? how about the mounts?  Everything snug/tight? 

 > did you look at any spent brass?  Anything odd?

 > did you chamber a round and see if there are any witness marks as if your LOA is too long?

 > what does the target tell you? 

 > did you ask the others with similar rifle what they were shooting?  Brand, OEM/Reloads, bullet style, powder, LOA, weight?...ect?

 > you can contact CZ and get their take on where to start if you want.   I got rid of all my 223s so i forget what works better in what twist ect.. but you can google for it. 

 > but as M1A4ME stated..... 

Guns are funny.  What works/shoots well in mine might not in yours.

   If you dont believe this, one day if/when you shoot enough you will.  Sorry, its the way it is.

 > reloading isnt always what you may have on hand as in supplies.  So All you can do is to workup some loads and see if something works - better - or not for your particular firearm.  Since you have some components, you can start there if you want.  Its up to you.

good luck

[Joe L]

I'll take a guess at the result.  The 69's worked well at the range, better than the 55's. 

But I'm a pistol shooter that owns one token AR .223 but it has a 1:7 twist and likes heavy bullets.  I think.  I haven't shot it in a while.

Joe

[m1a_scoutguy]

Try some 77-grain bullets, I have a bolt gun myself and the 77s shoot light years ahead of any 69 I have ever tried. The twist is 1/8 as you say which means it "should" like the heavies better. I wouldn't be in a rush to send it back to CZ until you put a solid try on it. Now you say Match ammo,, was it Hornady? I had a 243 and I NEVER could match up what a box of Hornady 243 Low Recoil ammo did out of that rifle, I got close but never could duplicate it I also tried Federal match and it was not as good as the Hornady. If it wasn't Hornady try a box if ya can find some. Please keep us posted on how ya make out.

[White Smoke]

Thanks for all the help and info. To answer some questions...I am a retired state trooper. 29 years. I am 85 YO and have been shooting all my like. I consider myself an EXCELLENT shot. I shoot 22LR competition and am usually shooting around 2200 out of 2500. Not bragging, but I am one of the top shooters in my club. I have been reloading since around 1955. I have had other people shoot groups and the results are the same, usually around 2" to 4" groups and usually just large round patterns, nothing like 4 tights and a flyer or anything like that. I do keep a log and everything is tight. I checked the bedding screws and they are TIGHT. The Leupold scope in on at 25# on the base and 15# on the rings. The scope I was using was on another rifle that shoots "lights out", but I did switch it out with another Leupold and nothing changed. The brass looks fine. I did get some pressure marks once when shooting a ladder, but nothing that would suggest anything wrong with the chamber, extractor or LOA is magazine length minus a couple of thousands for wiggle room. OAL is 2.22" using a Sierra 69-grain Tipped MatchKing bullet, 2.25" with the Hornady 55-grain V-max and 2.22" with the Barnes 55-grain MPG...all factory specs. Others in my club have CZ's and they all shoot great. I have tried everything I can think of. I just sent it back to CZ today. Let's see what they say. Again, thanks for all the comments and suggestions.

[Joe L]

White Smoke--
Thanks for the update and I sure hope CZ can get it fixed up for you!  And thanks for providing some additional background information.  I will be slinking out the back way and going back to my pistol now...
Joe

[Ron IL]

Way back in the old days when I got my AR I had a 20" 1:9 twist barrel.  I tested a lot of powder and ended up with one I liked and tested it iin 1/10 th grain increments.  By the Greenhill formula I needed a 69 grain bullet.  I used a Sierra Matchking 69 grain.  I used Reloder 15 25.5 grains if I remember.  I sandbagged  the rifle good and had a 24X scope.  I was making a 1/4 " hole at 200 yards.  That is all the range we had.  Then I got bored with it and gave it to my grandson.  He was getting ready to go to army bootcamp and wanted to learn the AR.

[M1A4ME]

Way back in the old days when I got my AR I had a 20" 1:9 twist barrel.  I tested a lot of powder and ended up with one I liked and tested it iin 1/10 th grain increments.  By the Greenhill formula I needed a 69 grain bullet.  I used a Sierra Matchking 69 grain.  I used Reloder 15 25.5 grains if I remember.  I sandbagged  the rifle good and had a 24X scope.  I was making a 1/4 " hole at 200 yards.  That is all the range we had.  Then I got bored with it and gave it to my grandson.  He was getting ready to go to army bootcamp and wanted to learn the AR.

I remember an "old guy" telling me about a Rock River Arms AR15 match rifle he owned.  He said it was so accurate he just got tired of shooting it and went back to shooting his Remington 03A3 at the range.  First time I ever ran into that outlook.  Then again, the best AR15 100 yd. group I ever shot was with a "nothing special" 20" HBAR clone I ended up giving to my oldest son who has taken it to the range once in 15 years.  So what do I know?

[Dan_69GTX]

White smoke - any update?

[White Smoke]

I just got the word this morning. They checked the rifle completely and shot it using Hornady 73gr ELD ammo. It failed at 1.25" MOA. They are sending me a new rifle. THANK YOU CZ!