Trying to get sub MOA with my CZ 527 in 223

[the count]

My local range has a benchrest group that competes once a month. Some pretty good shooters there. I recently got a new CZ 527 Varmint in 223 for the purpose of 100 yard target shooting. Today was the first time that I shot out to 100 yards (really only fooled around sighing in my 6-18X scope until now).

Twist is 1:9

I had 4 types of ammo.

#1- Cheap Russian Tula ammo, 55 grain. FMJ
#2- Hornady Match HPBT, 52 gr. over 24gr of H335
#3- Hornady V-Max 40 grain, moly over 24gr of H335
#4- Midway 'el cheapo' 55 grain FMJ bullet over 24gr of H335

Results....

@50 YARDS
#1 - 2.5"groups, #2 - 1.5" groups, #3 - 2" groups

@100 YARDS
#4 - 2.4" groups, #2 - 3.125" groups, #1 - 4" groups

The 50 yard results are probably only of minor interest as the BR club shoots 100 yards always.

Not sure what to do to get closer to 1 MOA (1")....? More powder, less powder, other bullets...? Surprising that the cheap 55 grain Midway bullets did best at 100 yards....

PS The trigger shouldn't be the problem as the CZ has a 'set trigger' feature where it is pushed ahead and just a couple ounces of pull will fire it.

 

[JDGray]

Depending on your twist, but for 7-10" Its hard to beat a 69gr SMK over a dose of Varget.

For the slower twist, try some 52gr SMKs , over that H335

CZs are known for accuracy, is the crown ok on that thing? Scope is mounted tight? Shooting in a good supported position? Scope is good?

 

[Rancho Relaxo]

Try some heavier bullets. My 1:12 527s love 50 grain bullets love 26-27 grains of H335. Seems odd that your rifle would be shooting that poorly.

 

[nipprdog]

my 6-18X scope

Brand??

 

[the count]

Try some heavier bullets. My 1:12 527s love 50 grain bullets love 26-27 grains of H335. Seems odd that your rifle would be shooting that poorly.

Hmmm, you might be on to something. I found this load data on reloadammo.com
My 24 grains might have just been too little. Will work up loads from 25 to 26...

52 grain JHP (Sierra Hollow Point, Boat-tail)
H335 26.0 gr. 3,300

 

[the count]

Brand??

Actually this is the scope currently mounted on that rifle.

Simmons Whitetail Classic Rifle Scope 6.5-20x 50mm Adjustable Objective Truplex Reticle Matte

 

[R.W.Dale]

Actually this is the scope currently mounted on that rifle.

Simmons Whitetail Classic Rifle Scope 6.5-20x 50mm Adjustable Objective Truplex Reticle Matte

try a different scope.

You can try different loads but your almost uniform lack of accuracy looks like a scope gone funky to me.

How many groups with each load did you fire? If more than one were they all equally bad?

 

[unwise11]

Going through a break in period most likely, be careful to make sure there is no fouling in the bore after a range trip.

 

[ifit]

some loads i tried out when i had my varmint kevlar
friend reloaded some ammo try out

these were shot at 100 yards all 3 shots ea. minus last target

this is my best 5 shot group since i had the varmint

what i found out, my 527 prefers lighter bullets

 

[R.W.Dale]

I just went and reviewed my records and it looks like my early model 527 Kevlar (1-12) was good for on average .9's @100 for 5 shots with great groups falling between .5 and.7 inches

Of course to you this means absolutely nothing as each rifle is different.

 

[millertyme]

A buddy of mine had a CZ in .204 Rug and it wouldn't shoot sub-MOA until he had some work done to the stock. Afterwards, however, you would have to try not to shoot sub-MOA.

 

[LiveLife]

Not sure what to do to get closer to 1 MOA (1")....? More powder, less powder, other bullets...?

count, I was at the range this afternoon doing some baseline testing with factory ammo for .223 and .308 Saiga and got the best just over 1" groups with Black Hills 55 gr FMJ.

 

[Logger]

Hey Count,

Is the barrel floated? Is the action pillar-bedded? That gun should shoot 50 cent piece sized groups or smaller. N

 

[the count]

Hey Count,

Is the barrel floated? Is the action pillar-bedded? That gun should shoot 50 cent piece sized groups or smaller. N

its a standard, out of the box 527 Varmint.

 

[the count]

some loads i tried out when i had my varmint kevlar
friend reloaded some ammo try out

these were shot at 100 yards all 3 shots ea. minus last target

this is my best 5 shot group since i had the varmint

what i found out, my 527 prefers lighter bullets

What was your powder and charge with the Sierra 55 HPBT?

 

[mc223]

If 52g Sierras over H 335 wont shoot, Check your scope and bedding.

 

[ifit]

i beleive it was win-748, as for the charge i have no idea as a friend reloaded for me a while back.

 

[stubbicatt]

Perhaps extending the range to 100 yards will render better results. It takes some time for bullets to "go to sleep."

Also a little more powder wouldn't hurt either.

 

[Fat_46]

My 527 in the same caliber took around 400 rounds before she settled in. I use 26.9gr H4895 over 52gr AMax bullets. The prairie dogs don't much care for this load, but I like it!

 

[the count]

If 52g Sierras over H 335 wont shoot, Check your scope and bedding.

I went over my rig after reading all these messages. Realized that my scope (Simmons Whitetail Classic Rifle Scope 6.5-20x 50mm) is mounted on high Leupold rings that I had to shim because the bell of the scope is huge. I used a couple layers of plastic (maybe 2-3mm thick in all) to shim both mounts equally. Since I am kinda new to shooting... is shimming a no-no when attempting target shooting? Might that explain part of my problem? I have a not so powerful Nikon ProStaff 3-9x40 Riflescope (Matte, BDC) that I could mount instead...

 

[TonyAngel]

First get the right mount set up. That's likely most of your problem. Are you sure that you are dialing out the parallax? You can't just set the scope to the labeled distance. You have to check and confirm the setting and make sure that you've properly adjusted the scope.

As for the load, try 24gr of reloader 15 under a 69gr SMK using good brass and a Remington benchrest primer. This load will give sub MOA groups in rifles capable of doing it. I've shot MANY sub MOA groups out of my AR15 using this load.

 

[30coupe]

I went over my rig after reading all these messages. Realized that my scope (Simmons Whitetail Classic Rifle Scope 6.5-20x 50mm) is mounted on high Leupold rings that I had to shim because the bell of the scope is huge. I used a couple layers of plastic (maybe 2-3mm thick in all) to shim both mounts equally. Since I am kinda new to shooting... is shimming a no-no when attempting target shooting? Might that explain part of my problem? I have a not so powerful Nikon ProStaff 3-9x40 Riflescope (Matte, BDC) that I could mount instead...

Shimming has been used for years, but I would not use plastic. Sheet brass is generally the shim of choice. If you have to shim 2-3 mm, I'd change to higher rings. I believe the 527 Varmint has a 1 in 9" twist rate, so it should work best with heavier bullets. As has been said though, rifles often have their own preferences. As poor as your groups are, though, I don't think its a bullet/load issue. You scope/mount would be a prime suspect, IMHO.

 

[Skyshot]

I had to bed and float my 527 it would only go about 2moa at 100. It now will shoot 1/2 moa with 50 grn and lighter bullets. The heavier stuff just will not group in my rifle, and we all know each rifle is different. I would also get rid of the plastic shims 1st, that might be your problem, I would try another scope also.