@ 12:44 am (GMT) |
Warrick EdmondsAll being said and done, I have to confess my fav rifle is my 1959 Brno 22Lr. My grandfather taught me to shoot with one and as soon as I could, I sourced my own. Its the same age as me. The only mods are a bedding job and a 2oz trigger, it'll print five shots off a pillow rest into 1cm at 50m. I took it up to the range last weekend for a play with various ammo. I usually fire subsonics for M/S comps, so its sighted in on those. I tried a subsonic hollow point hunting round and that was ok, I then tried a high velocity (1280ft/sec) hunting round and it grouped at the same drop as the subsonics but nearly 10cm to the right. I tried a diff high vel round and got the same result,.. 10cm to the right. So back to the subsonics for a reality check and they went dead straight, into the bull. I ran more high vel and they went right again. Odd !Any ideas? warrick |
@ 09:21 pm (GMT) |
Nathan FosterRe: 22Lr printnig sidewaysBuggered if I know Warrick. Try lying on your side. I bet if you shoot while on your side, the POI will be back on the verticle.The extension of this is to dive and roll on the ground and shoot at the same time. They do that in the movies, often with a firearm in each hand. Seriously, it is common to see changes in POI with various ammo. I know it's not normally too much of a horizontal shift with .22 ammo but your rifle is proof that it happens. Possibly less to do with barrel harmonics and more to do with bullet bearing surface and twist rate. Hard to say though. |
@ 10:49 pm (GMT) |
Warrick EdmondsRe: 22Lr printnig sidewaysOk, I'll give your advice a go, but a middle aged couch potato doing stunts aint going to be a pretty sight.I better warn the other guys at the range first or they'll be wondering what the hell is going on ! W |
@ 03:25 am (GMT) |
Martin SchmidRe: 22Lr printnig sidewaysHello Warrick,My bolt action .22 is sighted in for Winchester Super X. Subsonics (CCI, Remington etc.) more or less are just a drop down (but not quite). However, CCI Stinger and Aguila Super Maximum are drifting sideways substancially. Stinger goes to the right, Aguila to the left. Consistently. What makes it worse, it is enough deviation to miss a possum's head. My solutions was as follows: Using Hawke's Optics' Chairgun software for ballistics, I was optimizing my point blank range for Winchester Super X and sighted in accordingly. Then, I prepared for that distance little targets for all my other brands of ammo that I use. Now I have a little sheet with my ballistic table and diagrams of where the POI is for each brand, in relation to a POA sighted in for Super X. It works very well. Cheers |