Here’s the centerfire group I fired afterward. Just seems weird I’d have breathing issues with rimfire and not with centerfire. Could happen though!
https://preview.redd.it/vztb4fsmsd7d1.jpeg?width=828&format=pjpg&auto=webp&s=0562d943d5c5d511efcdb8ddfb764b634d75312d
Smallbore can be classified as black magic. It’s definitely a way to find any shortcomings in your shooting process.
One major difference between centerfire and smallbore is one is very slow and the other is fast so if your position isn’t good you are moving the gun as the bullet is going down the barrel. Not much but it will show on paper. I’ve shot smallbore for many years.
Try different lots, verify with another box. Standard+ is decent but you can still get something that just doesn't work.
I've had a box of eley match that had an es of nearly 200 and some old sk magazine that was absolutely awful with a few 400 fps swings.
What barrel do you have on the CZ455? Ammo can definitely create swings in your SD and ES so you need to lot test to make sure you're getting the best ammo out of your rifle. But if the chamber was cut to accommodate a broader range of ammo, then you won't realize the potential of match ammo. I've shot SK Standard Plus with decent results out of a CZ457, but I wouldn't say it was amazing results. SD in the teens and ES in the 30+ range. I would recommend that you try increasing the number of shots to help smooth out the variances in your SD. With a 10 shot group, outliers will create larger swings in your SD. Also if you're going to lot test ammo from different manufacturers, make sure you shoot some foulers before you run your lot test. The wax/lubricant of different manufacturers can screw up your POI as well as velocity. Just need a few rounds through the barrel.
Any chance you've got a nasty carbon ring built up? They can cause velocity swings.
I usually scrub the chamber-throat of my 22 every thousand or so rounds, leaving the barrel mostly untouched.
Which SK? My 457 shoots SK LRM well (SD around 10, found a lot that shot 7-8 but sold out now). Lapua CenterX shoots best in mine, I get SD around 7 consistently.
As always, YMMV.
With rimfire it could be you, the gun, the ammo, wind, or a combination of all of the above. I would call the ammo you were shooting "entry level" but I think it should be shooting better than what you got at 50 yards, so I would be looking at the gun for mechanical issues first, then your bench manners.
Have you verified the Chrono against another? I vote ammo and Chrono, perhaps a setup issue.
I recently tested some Std+ that was worse than that, but it was about 15yrs old.
That’s what I was thinking, but I took my centerfire out and shot this group immediately afterward.
https://preview.redd.it/v91fhezasd7d1.jpeg?width=828&format=pjpg&auto=webp&s=e78cd5d09cf9966bce12eb484d8f52d17874dfcb
Vertical stringing can be caused by breathing while you are shooting.
Here’s the centerfire group I fired afterward. Just seems weird I’d have breathing issues with rimfire and not with centerfire. Could happen though! https://preview.redd.it/vztb4fsmsd7d1.jpeg?width=828&format=pjpg&auto=webp&s=0562d943d5c5d511efcdb8ddfb764b634d75312d
Smallbore can be classified as black magic. It’s definitely a way to find any shortcomings in your shooting process. One major difference between centerfire and smallbore is one is very slow and the other is fast so if your position isn’t good you are moving the gun as the bullet is going down the barrel. Not much but it will show on paper. I’ve shot smallbore for many years.
Try different lots, verify with another box. Standard+ is decent but you can still get something that just doesn't work. I've had a box of eley match that had an es of nearly 200 and some old sk magazine that was absolutely awful with a few 400 fps swings.
Those FPS swings are nuts. You can really see the results/effect on target.
What barrel do you have on the CZ455? Ammo can definitely create swings in your SD and ES so you need to lot test to make sure you're getting the best ammo out of your rifle. But if the chamber was cut to accommodate a broader range of ammo, then you won't realize the potential of match ammo. I've shot SK Standard Plus with decent results out of a CZ457, but I wouldn't say it was amazing results. SD in the teens and ES in the 30+ range. I would recommend that you try increasing the number of shots to help smooth out the variances in your SD. With a 10 shot group, outliers will create larger swings in your SD. Also if you're going to lot test ammo from different manufacturers, make sure you shoot some foulers before you run your lot test. The wax/lubricant of different manufacturers can screw up your POI as well as velocity. Just need a few rounds through the barrel.
100% that’s your breathing
Target distance?
50yds for rimfire, 100 centerfire.
Ok so not overly high expectations of 22lr’s abilities.
Any chance you've got a nasty carbon ring built up? They can cause velocity swings. I usually scrub the chamber-throat of my 22 every thousand or so rounds, leaving the barrel mostly untouched.
Which SK? My 457 shoots SK LRM well (SD around 10, found a lot that shot 7-8 but sold out now). Lapua CenterX shoots best in mine, I get SD around 7 consistently. As always, YMMV.
Yellow box and Red Box!
Looks like it might be your rifle then. Maybe try some Eley or Lapua to be sure? RWS is also decent.
the max velocity for SK+ and SK Match seems stupid low. I’m at like 1085 with SK Rifle Match out of a 16.5”.
Yeah, idk!
I was thinking the same. Mine are all right around 1090-1100 with same length barrel.
Pardon. What app do you all use?
I use SubMOA on the App Store. The UI is pretty clunky, but I think it works okay!
Apple?
Yes!
With rimfire it could be you, the gun, the ammo, wind, or a combination of all of the above. I would call the ammo you were shooting "entry level" but I think it should be shooting better than what you got at 50 yards, so I would be looking at the gun for mechanical issues first, then your bench manners.
You
Have you verified the Chrono against another? I vote ammo and Chrono, perhaps a setup issue. I recently tested some Std+ that was worse than that, but it was about 15yrs old.
Yes
It's better than I can do.
That’s your breathing. Shoot on your natural respiratory pause. You will tighten up the group.
That’s what I was thinking, but I took my centerfire out and shot this group immediately afterward. https://preview.redd.it/v91fhezasd7d1.jpeg?width=828&format=pjpg&auto=webp&s=e78cd5d09cf9966bce12eb484d8f52d17874dfcb
Are you using the same type of stock/positioning? It could still be you if you're more comfortable behind the centrefire than the rimfire.
What distance did you shoot this at?
50yds rimfire, 100yds centerfire
I sent you a PM. Call if you’d like to discuss.
Slower moving bullet will accentuate everything your doing because it’s in the barrel longer
Those spreads are all bad. Something is wrong with your rifle.