CZ 457 22lr fun--windy day

[stagpanther]

Took out my back-up CZ rifle for some fun in the sun; the forecast was for light winds in the 5 to 7 mph range. Instead, it was very windy15 to 20+ and gusty from all directions--happens often here on the coast when an onshore breeze collides with a front dropping in from Canada. I also had my 257 weatherby along to test a new load using 7828 SSC and 120 gr seneca bullets. Considering the windy conditions I decided to back off the distance to 138 yards to minimize the effect of the winds. The 257 load performed, in a word, terrible--a shotshell of birdshot at that distance would be embarrassed. I knew my 22 lr bullets would be pushed all over the place and decided to go with lapua long range. The group it produced isn't good in terms of precision 22lr shooting, but for gusty variable winds I was actually quite impressed; beat the pants off the 120 gr high SD bullets I was firing at 3,400+ fps.

[Pumpkin]

Incredible! So much for time of flight vs wind drift.

[stagpanther]

Incredible! So much for time of flight vs wind drift.

It really depends on the nature of the wind and the topography around the distance from shooter to target. When I shot the group above at 138 yards, around 2:00pm, there was also a lot of convective activity (heating of the ground causing air to rise) so in a way that "cancels out" to some extent the stringing you might expect to see vertically. The lapua long range seemed to do quite well with the gusts which were coming more from the sides--hence the horizontal drift. It did well with the relatively short distance of 138 yards--not so well when I shot it again out of my other 22lr CZ

Late this afternoon I also took out my #1 22lr rifle; my CZ 457 jaguar which has a 28" barrel. Winds had calmed down significantly to around 7 to 12; but had swung around so that I was shooting directly into the wind at 191 yards. Most of the different ammos faltered and strung out significantly vertically, lapua's long range and X act both strung pretty large vertical groups. The best performance was turned in by Eley Tenex, no surprise to me since it and RWS 100 have always been the top performers through this particular rifle at distances around 200 yards or more.

This group of Tenex beat the long range and x-act by a significant margin. It also was shot while the winds were stronger than when I shot the later groups of other ammo. I rotated the image horizontally so I could get it scored by Balistic X, the two shots on the top margin that are not scored are shots that dropped in from the x-act group.



What a lot of shooters might not know--and might have trouble believing--is that in reality the bullet profile for subsonic/almost subsonic 22lr bullets are some of the most efficient bullet designs when it comes to rate of velocity loss due to drag.

PS--the actual POA for this group was slightly off the picture border.

[Pumpkin]

That is really impressive! My hat is off to you.

I had no idea that a 22 could do that, obviously, not just any gun or shooter. ;-)

My most impressive feat was a sub 1/2” five shot 50 yd group from my sand bagged M39A with some Winchester Super X HP’s. The rifle has a 24” bbl and a Williams receiver sight.
That was done about 25yrs ago.

[nuchie11]

Good call dropping to 138 yards with that wind. The 257 Weatherby load with 7828 SSC and 120 gr bullets just isn’t stable in gusty conditions, too light and fast. Lapua Long Range .22 LR handles wind better, so your results make sense.
For the 257, try heavier bullets with higher BC and slower powders for more stability. Always test loads before windy days to avoid surprises.

[stagpanther]

Good call dropping to 138 yards with that wind. The 257 Weatherby load with 7828 SSC and 120 gr bullets just isn’t stable in gusty conditions, too light and fast. Lapua Long Range .22 LR handles wind better, so your results make sense.
For the 257, try heavier bullets with higher BC and slower powders for more stability. Always test loads before windy days to avoid surprises.

Where I live it's impossible for me to "read the wind"--as if it comes from just one direction at one velocity constantly. That almost never happens. So instead I try to pick the cycles. I learned to do this from over 25 years experience as a foot-launch hang glider and paraglider pilot. Wind generally has up and down cycles that you can time; in other words look for a rhythm to the cycles. I have better luck trying to shoot in near duplicate conditions as opposed to adjusting windage/elevation for how far off the POI is from the POA--if that makes sense.

I did a "post mortem" on my failed 257 wm load this morning when I cleaned and examined the bore. There were a couple of spots with heavy accumulations of copper (I only shot 7 cartridges off a completely cold clean bore) and it looked like the bullets may have ripped across the lands and grooves in those spots. I generally get excellent results with hornady eldm's--they are a bit heavier and slower at 134 grs and 3,200+ fps. I bought 500 of the senecas a couple years ago, and to be honest have yet to find good load for them in any of my quarter bores--I originally got them for my 25 PRC blackjack build. PVA publishes these figures:

Optimal Freebore: 0.150"-0.200"

G1 BC average = 0.640*

G7 BC average = 0.310*

Obviously the freebore and velocity on my 257 weatherby might be part of the problem, though in my 25 PRC I did explore the optimal settings and still didn't find a sweet spot.

[stagpanther]

This is my back-up CZ 457. It's going to get some upgrades this summer and I'll be interested to see how it does compared to my jaguar. The scope just came off my 257 weatherby; I've put it away for the time being having burned through lots of expensive powder and bullets.