This is a helluva lot of results that deserves more "advertising". Was the firing from a bench rest for consistancy? Certainly is a great advertisement for BRNO.
Thank you for sharing this.

Yes, all shooting is done in an indoor shooting range, off the bench. We installed a Bushnell Elite 4200 6-24 X scope on the rifle.

100 yards results will follow.

saeed - have you tried the american eagle ammo that federal makes? its cheap stuff, but in my tests it came out to be one of the most consistent brands across a variety of guns

Had the same kind of results with 1 Lux, 4 Sporters and 3 Varmints. The top of the line Eley, Lapua, Old Federal showed the best results. We shot outdoors, but the results you
show mirror our results.

We were shootinf off the bench and shooting the RBA 25 bull target when we werent shooting groups. The CZ would occasionally shoot a low 240 out of 250 but surely in the high 230s most of the time. A good bench 22LR will shoot in the mid 240s all of the time. I have shot numerous sub .250 groups (5) at 50 yards.

We started at 100 and if you can break 1" you are doing well. Shot only a couple of sub 1/2"
groups at 100, with a Kimber HS. If you delve into the 22LR realm, start with the most accurate ammo listed above as a start point.
Expensive, you betcha. but .99 Cent a box ammo will not cut it. Shot many bricks of various
ammo to prove that. It will be the most frustrating thing you will ever do.

Estacado

Some interesting things have come up with this rifle.

At 50 yards, there was very little change between point of aim and point of impact with different ammo. Even standard velocity and high velocity seem to hit in the same general area on the target.

With the Walther KK200 for instance, the difference vertically between standard velocity and high velocity was as much as 4 inches vertically!

Now, we are shooting this rifle at 100 yards. With this one, there seems to be a definite, and marked, change in the point of impcat relative to the velocity of the round. Even a little chance seem to make a difference.

We have had this with the other rifles, but with this one it seems to be much more pronounced.

Walter thought we should try his converted BRNO 452, fitted with a silencer of his own design, after the barrel was cut to 12.5 inches.

Well, we seem to have lost about 300 fps from the standard velocity ammo. What used to give us 1100 fps now only goes around 800 fps.

So we have decided to test this rifle at 25 yards only, at Walters request.

It is going to be next in line after I finish this one.

Those are excellent groups with a sporter.
Good shooting, and thanks for sharing the results.

Don

We have finished shooting this rifle at both 50 and 100 yards.

Next is going to be Walter's custom silenced BRNO 452. Walter insisted that we only shoot it at 25 yards.

My "sound attenuator" does not totally silence for that is illegal in the US. But it does quiet things down a bit and the ammo I have the best accuracy at 25 yards is, of all things, Aguila .22-SSS(Sniper Sub Sonic). All holes touch using an old Remington 511 with the barrel cut to 16 inches and using a Weaver 2.5 post scope. The Agila is a solid, so I make it a large hollow point and end up with 925+/-.
Be interesting to see your results.

The barrel on our is 12.5 inches long, and we seem to have lost about 300 fps from standard velocity ammo.

We will start things rolling today, and see how things work out.