Accuracy Expectation for CZ 455? Training tool for PRS

[308pirate]

Ballistic chronographs are tools Rick.
You can spend a lot, or spend a little.
I use a Pal chronograph. Basic optical sensor model.
I record single shots in my log book when testing centerfire handloads.
Use the high, low and average when testing rimfire for 50 shots.
All I really care about is the extreme spread.
The standard deviation has no value for my purposes.
I don't care about my average results, I care about worst results.

+1

The emphasis on standard deviation and the lack of focus on extreme spread shows who understands statistics and who doesn't.

 

[richthe1]

Thank you all for the comments and advice - I’ve read through all of them and appreciate the insight.

I finally got to take it out. I shot 47 five shot groups of CCI SV at 50yds for an average group size of 0.68”. I then cleaned the rifle and shot 14 five shot groups of Norma Tac 22 at 50yds for, coincidentally, an average group size of 0.68”. I was initially disappointed - I was really hoping for a consistent 1MOA at 50yds.

I had a limited amount of time remaining at the range, so I decided to try a box of SK STD+ before I left. I was very pleased with how consistently it grouped, although I only got to fire 40rds before I had to leave.

It was embarrassing to have that 1” group as my final 8th group, but the good thing was I could tell I was rushing my shots (poor trigger control) trying to finish up and get out of the cold weather.

I only have 60rds left of SK STD+ left. I’m considering purchasing more SK STD+ from the same online vendor, but they don’t guarantee I’ll get the same lot # - is this a big concern?

 

[brettitt41]

My CZ likes SK+ & SK rifle match even more. It shoots CCI standard like a shotgun though. I use SK+ for my everyday shooting and practice and rifle match for comps.

 

[Tiger_Shilone]

Thank you all for the comments and advice - I’ve read through all of them and appreciate the insight.

I finally got to take it out. I shot 47 five shot groups of CCI SV at 50yds for an average group size of 0.68”. I then cleaned the rifle and shot 14 five shot groups of Norma Tac 22 at 50yds for, coincidentally, an average group size of 0.68”. I was initially disappointed - I was really hoping for a consistent 1MOA at 50yds.

I had a limited amount of time remaining at the range, so I decided to try a box of SK STD+ before I left. I was very pleased with how consistently it grouped, although I only got to fire 40rds before I had to leave.
It was embarrassing to have that 1” group as my final 8th group, but the good thing was I could tell I was rushing my shots (poor trigger control) trying to finish up and get out of the cold weather.

I only have 60rds left of SK STD+ left. I’m considering purchasing more SK STD+ from the same online vendor, but they don’t guarantee I’ll get the same lot # - is this a big concern?

That is pretty typical of 22LR ammo. The more you pay the better the quality (quality meaning less extreme spreads, more consistent std dev and less "random flyers"). It's unfortunate, but that is the reality. Also, domestic 22 ammo sucks, everyone who is serious is buying foreign ammo from germany , finland or britain. All the "domestic match" ammo that shoots good is relabeled foreign ammo. The best domestic ammo is CCI SV 40 gr round nose. I've tried CCI green tag and it was no different in results than SV. CCI is the only domestic ammo I'll use, but the 3-6 turds in each box of 50 irritate me enough to never use it in a match. Good for plinking or an Appleseed clinic. I chrono every round at benchrest matches and have accumulated data on the following in my opinions:

For the Lapua family of bullets I use SK Standard+ for plinking and shooting NRA standing silhouette matches. For steel or PRS/NRL style matches I step up to SK Rifle Plus and Center-X. For ARA rimfire benchrest matches I use Center-X, I was using Midas+, but it wasn't enough of a performance gain for the price increase to justify.

Wolf branded ammo used to be made by SK and the two tiers were equivalent to SK+ and SK Rifle match. They were literally made on the same production lines but were packaged and labeled for different end users. Wolf quit their contract with SK in 2017 and has since moved over to ELEY to make their 22 products. I have no experience with the current Wolf/ELEY ammo.

ELEY out of britain has several lines of varying quality 22 ammo. I've used ELEY Black box FORCE with good results for Steel and PRS/NRL, it is a fast round bordering on supersonic so if you are at low altitude on a cold day this could get sonic cracks with the subsequent loss of accuracy. I rate it the equivalent of Lapua Center-x. I've also used TENEX for benchrest, found it to be slightly better than Lapua Center-X at a much higher cost. No Recent experience with their lower grade lines like club.

RWS-50 I like a lot, find it to be a little better than Center-X, but just by a little, price is higher.

This is across 10+ different rifles----Vudoo, CZ455, KIDD, Ruger, MArtini, PWS, Anschutz. Depending on the rifle and budget, some have chambers orientated towards one brand of ammo, this is more of a consideration in the benchrest world where you need to shoot in the .2oo" or better to be competitive.

EDIT TO ADD: My CZ455 likes both SK products and the ELEY Force. I tried using the 455 in benchrest for a couple of years, but even with good ammo it wasn't competitive, hence the Vudoo and Anschutz get that duty.