.308 long range load development results

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I have a question but bear with me.

I’m signed up for an F-TR match this Sunday that is 20 shots each at 300/500/600 yards. 2 sighters per.

I was going to load up the Berger 185g load with H4895 that I’ve been working on and realize I don’t have enough bullets.

I can fall back to the 180g Sierra load with Varget but that load was on the hot side and wearing out the primer pockets.

So I decide to do some last minute load testing with the 180g SMKs using H4895. Cutting to the chase, 42.5g looked good and I made enough to shoot 20 at 500 and got this 20 shot group.,,

AC11F981-4049-476A-92B9-CEDF03B435BB.jpg

Thats the best group I’ve ever shot at that distance (sub MOA), but it’s right of POA

My question:

Wind was nil. My 100 yard zero was centered on POA. Is the difference between POA and POI spin drift?
 
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Wind was nil. My 100 yard zero was centered on POA. Is the difference between POA and POI spin drift?

That's a good group for sure and estimating the distance of the group center from the center of the target it looks to be around 1-1/4" which is consistent with spin drift for a good 180gr .30 cal bullet from a .308 Win with a RH twist barrel at 500 yards. I use the Applied Ballistics app on my phone and always have the spin drift box checked.

@Nature Boy , I enjoy following your threads and seeing how well you're doing with load development and shooting. It's quite inspirational. Good job!!
 
I appreciate your input @MCMXI

I’m always hopefully that you will respond with advice.

I’m using the Ballistics AE app on my phone but I’m not taking spin drift into the equation. When you’re just dicking around its fine, but when you have to shoot for record and you’re only allowed 2 sighters all of a sudden the minutia matters
 
Yep spin drift. Go figure

Distance to center of the group: 1.53”

86D3569E-8F45-498B-9839-79F22E9199DC.png

Plugged the pertinent data into the spin drift calculator and sure enough it shows 1.63” at 500 yards.

BFB7EEB8-B9E9-4783-B26E-91795374C086.png

For those that are interested, here’s my load data

180g Sierra Matchking
42.5g H4895
Lapua brass (these were new, run through the sizer)
OAL 2.825, .005 off the lands

Here’s the chrono data

C5E029C6-5E97-4697-BA91-07EE63A0B936.jpg

And the rifle in competition trim ;)

672541F4-2B37-43AC-B6FF-54D31E443B13.jpg
 
My first rifle match is in the books

F Class Mid Range 300/500/600 yards

Shot a 582 16x, good enough for Master classification. All 9’s, 10’s and X’s.

Thanks to you guys in helping me sort out my loads and assorting advice. Now I’m hooked

Oh, and 9 X’s at 600 :thumbup:
 
That's some fine shooting, especially for a first outing, NB! Congratulations.

Regards,
hps
 
Nice shooting for your first time out.

Now you have to start stocking up on supplies so you have all your match ammo ready to go. This way you want have to be switching bullets at the last minute.
 
Very nice development. I agree with the other guys, this is one of those threads that provides good quality
information and pics and adds value to the knowledge base.
So many thanks for taking the time to document your progress. I know these things can be time consuming.
 
I'm going to say barrel harmonics differences between the 180gr and 185gr. Different bore-bearing surfaces will cause those shifts in poi.
 
Thanks Nature Boy for the excellent thread! I too have been stretching my 24” .308 at further distances, no where near 1k yet though.

I’m curious if you looked at loading tipped MatchKings or the ELD-X bullets for their higher BC. I’m currently loading 168g HPBT at 2,764fps, but at 500 yards and further I’m looking at better options. Are the tipped bullets being used much by competitors?

Excellent shooting and I hope you find the time to continue to post your progress.
 
Shot a 582 16x, good enough for Master classification. All 9’s, 10’s and X’s.

@Nature Boy, that's outstanding! F-Class is addictive for sure. :) Congratulations on such a good first outing. Out of interest, which string was the toughest for you? I always found the 300 yard stage to be the most intimidating.
 
@Nature Boy, that's outstanding! F-Class is addictive for sure. :) Congratulations on such a good first outing. Out of interest, which string was the toughest for you? I always found the 300 yard stage to be the most intimidating.

Hard to say. Less wind during 300 yard stage but more nervous. I dropped less shots but fewer X’s

Wind had picked up by the time I shot 500 and 600. More 9’s but also more X’s

96665C6C-B9A5-4847-92C0-37C472F567C2.jpg
 
Got another match under my belt today. Managed to improve from last month, which is my goal

Shot a 588 25x
68A1582B-178A-4D2A-916B-40F855DAEEF0.jpg

More X’s, Less 9’s. Hope its a trend.

Leading up to this weekend I resisted the urge to tweak my load and stuck with what I shot last month. Instead I practiced shooting at 500 yards and worked on my trigger mechanics and position behind the rifle.

All of my 9’s were left or right. My verticle spread at 300/500/600 yards is sub MOA

I’m convinced the main issue causing me to drop shots isn’t the wind, it’s all me and my interface with the rifle. I have to reposition myself after every shot. Recoil is moving me off target left or right. I’m not getting the rifle to track straight back. That’s not helping my consistency
 
Got another match under my belt today. Managed to improve from last month, which is my goal

Shot a 588 25x
View attachment 774080

More X’s, Less 9’s. Hope its a trend.

Leading up to this weekend I resisted the urge to tweak my load and stuck with what I shot last month. Instead I practiced shooting at 500 yards and worked on my trigger mechanics and position behind the rifle.

All of my 9’s were left or right. My verticle spread at 300/500/600 yards is sub MOA

I’m convinced the main issue causing me to drop shots isn’t the wind, it’s all me and my interface with the rifle. I have to reposition myself after every shot. Recoil is moving me off target left or right. I’m not getting the rifle to track straight back. That’s not helping my consistency

Good shooting! Might try to "straighten out your position" and pay very close attention to natural aim point. Been a lot of years, but when I shot NRA XTC matches, was having similar LR problems. I shot prone w/body at probably 35*?? angle to axis of rifle. Made an effort to get straight behind the rifle and that made for more solid position & reduced tendency of right elbow moving from recoil (if that makes sense). Also paid a lot more attention to achieving better NPA before each shot. Still lost a few to mirage that I missed, but seemed to be a steadier position.

Regards,
hps
 
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