1100+ yards with the 300 wsm

[Orr89rocz]

Did a quick 5 shot group today at about 1100-1150 ish yards. Light drizzle/misty rain but wind was basically dead. Occassional slight breeze up by the target.

Gun is my savage 11 based 300 wsm. 24" brux bull. Off the bipod with a weaver tactical 5-15x50mm mil/mil
Shooting 185 gr bergers juggernauts

First real attempt to group. I've shot this range 1 time before with somewhat similar results on a cardboard box.
Took 2 to dial on target. Took more adjustment this time conpared to warmer dry spring air. It was 37 deg today.

http://i1339.photobucket.com/albums/o720/Orr89rocz/Mobile%20Uploads/image_zpsf738c0dc.jpg (http://s1339.photobucket.com/user/Orr89rocz/media/Mobile%20Uploads/image_zpsf738c0dc.jpg.html)

http://i1339.photobucket.com/albums/o720/Orr89rocz/Mobile%20Uploads/image_zps8c19bfde.jpg (http://s1339.photobucket.com/user/Orr89rocz/media/Mobile%20Uploads/image_zps8c19bfde.jpg.html)
Shooting just below that far tree cluster on the middle horizon

[Lbass]

If I can hit that well with mine when I get it done you'll be able to hear me giggle, yes, giggle from where you are.

[Orr89rocz]

Doing some searching here i see that temperature can have a greater impact on velocity than i originally thought and would explain why i needed approximately 2 mils more height adjustment to reach target than in the dry warm air. Seems to be a significant difference. May try testing ammo left outside vs warm ammo in my pocket to see how velocity changes with this powder

[Lbass]

That much of a change in point of impact got me interested, so I ran some numbers through hornady's ballistic calculator. The numbers I used humidity didnt seem to matter much. Temperature made quite a bit of difference at the distance you're shooting. Denser air I guess... I use alot of RL-22 which is said to be temp sensitive, but most of my shooting is 600 or less and temperatures havent been a problem... Looks like I'll have quite a learning curve stretching my legs to 1000. Let us know if keeping the ammo warm does much, that would at least take out powder sensitivity as a variable.

[js223]

I'd guess that the elevation difference you experienced was due to a combination of lower muzzle velocity from the cold ammo and more drag from the denser atmosphere.

[seanhagerty]

I have gone off the deep end on mid range shooting the last couple years. (Out to about 1100 yds). I have found exactly what you speak of. Colder weather means more dense air, so more elevation is needed.

Two things I have done to account for this:

I have switched to a temp insensitive powder. No worries about temp swings, the velocity stays the same. This is a huge deal. I cant imagine how difficult life would be having to have diff velocity data for my loads also.
Instead of just accounting for temps changes in atmosphere conditions, I use density altitude. It takes into account all things that change how dense the air is.


Using Density Altitude (DA) has made my life easier at the 500ish -1100 yd ranges. Closer than 500 I dont see much difference based on DA. The trick is how do I calculate DA?? I dont. I use an app for my phone. I have played with this enough that I can get close based on temp and altitude where I am at. I also put together a dope card that has elev corrections for different DA's, 0 ft, 1000 ft, 3000 ft, and 5000 feet. The card looks like an insurance actuarial spreadsheet, but i have played with enough to know how it works and can use it fast. I put together the drop data on the jbm data site and pulled it all into one spread sheet. I have about ten of these data cards mixed into my gear. I also had them laminated, (after I had verified the data.)

The proof is in how repeatable this approach is.

[eddiesindian]

Dam straight

[D.ID]

Nicely done and one perdy stock to.
I ran 190s in mine.
My elk hunting partner started using 230s in his wsm this last year.
He's spot on and lethal at 1K.....couldn't shoot for sh!# past four hundred a few years ago, now he never misses. I was pretty surprised how well they have performed at modest speeds.

[NW Hunter]

I did load development with my 300WM and RL-22 once. It loved all bullets! I did development in the spring and by summer, warm air temps made the load go overpressure. I happily shoot H 1000 now. Loves 190 to 210 Berger VLDs.

[limige]

try H4350