.308 long range load development results

[Nature Boy]

Pretty cool @hps1

 

[Nature Boy]

Corrected my bonehead mistake and got the bullets I really wanted to try in the mail today (on the right)



Both 200g .308 SMKs but obviously a big difference

 

[z7]

NB

Let us know how that works out, those suckers are LONG!

 

[Nature Boy]

NB

Let us know how that works out, those suckers are LONG!

I’m pessimistic that they will work for my rifle but I’ll have an answer by the end of the weekend

 

[Nature Boy]

Well, I did it again. Stopped at the range on the way to work. (Its a sickness!)

Sierra just put out their load data this week for these new 200g SMKs. Standard disclaimers apply. My loads are over their max (by 2.0g) so use your own discretion. I stuck with H4895



These bullets are LONG. When seated to touch the lands I get 3.070”. Here’s a comparison with the 185 Berger Juggernaut, which is also a long bullet



They aren’t very practical in my Mausingfield. It’s not throated for these long bullets, they are too long to clear the ejection port (I guess you’d need a long action), my barrel is a 1:10 twist and Sierra says that might be too slow.

In any event I press on. Here’s the target



Could be a node between 41.0-41.5, similar to the old 200g SMKs on the previous page. Varget might be a better powder. The promise of having a 700+ BC bullet in .308win may keep me testing. We’ll see.

 

[hps1]

Well, I did it again. Stopped at the range on the way to work. (Its a sickness!)

Could be a node between 41.0-41.5, similar to the old 200g SMKs on the previous page. Varget might be a better powder. The promise of having a 700+ BC bullet in .308win may keep me testing. We’ll see.

39.5-40 doesn't look all that bad, either.

4895 has always been an excellent choice in 308/30-06, especially w/lighter bullets (>175 gr). Not sure how it would work in the 308, but I used H450 behind 190 gr. SMK's back in the day for 600 yds. and out. It's a shame they have discontinued that powder as it was great w/heavier bullets in the 06.
Can't get quite the velocity out of it that you can w/4895 or 4350, but it was most accurate load I found.

Regards,
hps

 

[Blue68f100]

H4895 is a little fast for that heavy bullet. I would try IMR 4451 Induron powder since it's not sensitive to temperature, and give you max velocity. Or H4350 is another that is pretty temp stable, one of their Extreme Powders.

Nice shooting as always with you.

You would go nuts it my place since I have my own range. But not as long as you like. But I'm working on that, just have some more clearing to do.

 

[Nature Boy]

I meant to add this pic of the cases, which to my uncalibrated eye look fine pressure wise. I also didn’t encounter any bolt lift or extraction issue. I’m always a bit nervous when operating outside published guidelines

 

[Blue68f100]

I don't see any indications of over pressure on those at all. You could probably go up some more on the charge if needed.

 

[Nature Boy]

I got out this morning and finished up testing these long 200g SMKs going 0.5g higher than where I left off above. Here’s what it looled like



Still no pressure signs at 42.5 but obviously the vertical deviation between 42.0-42.5 would indicate there’s no accuracy node there.

Still looks like 41.0-41.5 would be the best. Here’s a comparison between this time and last that shows the consistency of this method, however, today’s velocitys were noticeably slower. Not sure why. Today on top, a few weeks ago on the bottom



I think I’m going to call it quits on this bullet. I don’t see much value with them being so long that they won’t eject out of a short action rife. It was still worth trying.

If anyone would like to try them in a 300 win mag, or 30-06 even, I’d be happy to send you what I have left. Shoot me a PM

 

[Nature Boy]

I’m continuing the hunt for a higher BC bullet that I can get to shoot at longer ranges. Having crapped out on the 200g options so far, I looked at the Berger catalog and decided to try the 185 Hybrid.



What I’ve found as I try these 185s in various configurations and makes is that the accuracy nodes tend to reveal themselves at similar speeds, generally around 2,690-ish FPS. With that in mind I took a chance and loaded some of these 185 hybrids with the same powder charge I used for the Juggernauts and went straight to 500 yards.

Sighters validated what the ballistics app told me, 0.2 mils less elevation at 500 yards. I proceeded to put the remaining 10 rounds into this target.



This is good enough to warrant some more load development, but it also highlights the need for more shooter development. Each time I broke the shot I knew the ones that were going to be left or right of the center, either due to recoil management or trigger control. I’ve got to keep working on that

 

[Nature Boy]

I did some more fine tuning on these 185 Berger Hybrids after work. Here’s the results



I went with 0.3g spreads and it looks like 2 nodes, one between 42.4 - 42.7 and the other between 43.3 - 43.6

I also found in interesting that the group where the node fell off, 43.0, also had the most deviation in FPS between the adjacent groups.

I think I’ll load up some at 43.5 and see how they do at 500 yards tomorrow

 

[Derek Zeanah]

Here's where my inexperience pops up: I'd just load 42.7gr and call it good.

 

[horsey300]

I’m continuing the hunt for a higher BC bullet that I can get to shoot at longer ranges. Having crapped out on the 200g options so far, I looked at the Berger catalog and decided to try the 185 Hybrid.

View attachment 782009

What I’ve found as I try these 185s in various configurations and makes is that the accuracy nodes tend to reveal themselves at similar speeds, generally around 2,690-ish FPS. With that in mind I took a chance and loaded some of these 185 hybrids with the same powder charge I used for the Juggernauts and went straight to 500 yards.

Sighters validated what the ballistics app told me, 0.2 mils less elevation at 500 yards. I proceeded to put the remaining 10 rounds into this target.

View attachment 782010

This is good enough to warrant some more load development, but it also highlights the need for more shooter development. Each time I broke the shot I knew the ones that were going to be left or right of the center, either due to recoil management or trigger control. I’ve got to keep working on that

For higher bc (keeping in mind that I don't remember your twist rate for stability) have you looked at the 180 elite hunters? They're right up there with sierra's 195 tmk......just saying

 

[Nature Boy]

Here's where my inexperience pops up: I'd just load 42.7gr and call it good.

Hey, I’m learning too Derek.

Using this method you’re looking for vertical deviation between adjacent group centers, not necessarily the smallest group. 42.7g is in a node, but looking at the change in vertical between it and 43.0g it might be on the edge. Go over a little bit in powder throw or shoot on a hot texas summer day and you might find yourself pushed into that node.

I went up to the next apparent node between 43.3 and 43.6 with hopes that the additional velocity gives me more of an advantage at longer distances. I also don’t want to be on the lower end for the same reason: I want to avoid 43.0

 

[LoonWulf]

I have a partial box of 208 eld-m, if you wanna try those. Bought them for my last go round with the .300
My 06 shot them ok, but not as well as the lighter 178s.

 

[Nature Boy]

I got this 185 Berger Hybrid out to 500 yards today using 43.5g of H4895. Here’s how the target looked after 20 rounds



No wind today but there was a light mist falling. I pretty happy with this. 0.2 mil less elevation than the 185 Juggernauts and 1/2 inch less wind drift.

Honestly, my load development has become less about the load and more about my controlling the rifle.

 

[Derek Zeanah]

Honestly, my load development has become less about the load and more about my controlling the rifle.

That ain't a bad thing.

Outstanding job there.

 

[bikemutt]

Honestly, my load development has become less about the load and more about my controlling the rifle.

You're doing a great job!

I would really like to hear more about controlling the rifle part, maybe a different thread.

 

[Nature Boy]

I would really like to hear more about controlling the rifle part, maybe a different thread.

It would probably be good topic to have it's own thread. Maybe I'll start one over in the Competition Forum specific to F Class since that's where my precision/accuracy focus has been.

I think we've chewed all the flavor out of this one.

I’ll finish with this. I had 5 rounds left over so I stuck a 3” target on a piece of paper to see if I could put all 5 inside of it. I focused on my concentration, breathing, trigger control and recoil management. Here’s how it looked



It may sound odd, but I knew where each shot was going to end up before it hit the target. The 2 shots dead center were the result of a combination off all those factors I mentioned coming together. The ones left and right of the target were trigger control and recoil. At the moment shot broke I detected a slight movement off POA and sure enough, that’s where it went. I won’t fix that on the loading bench

 

[Nature Boy]

Got up early to get some practice at 500 yards with the 185 hybrid load noted above. It was raining with wind gusts at 12 o’clock. Not the best day to work on form for sure but I’m shooting a mid range match tomorrow so I wanted to get some time behind the rifle.

I’ve been practicing dry firing on the living room floor and made a couple of changes to my position. I generally like a firm cheek weld but I adjusted the riser and tried a little lighter contact with the rifle. I also worked on having my shoulder in the same place prior to pulling the trigger. Cutting to the chase here’s the results. 10 shots on a 3” target at 500 yards:



Big improvement. I noticed less movement off target during recoil and less repositioning after each shot. We will see if it translates to better scores tomorrow. This 10 shot group measured 0.45 MOA

 

[Stevenvalleyky]

Tremendous shooting @Nature Boy. While your set up adjustments have obviously helped, before these changes, you were shooting long range groups that were smaller than 90% of everyone else on THR would be able to accomplish. Great job.

 

[Walkalong]

10 shots on a 3” target at 500 yards:

That will work right there. Very nice.

 

[Walkalong]

This goes to show what practice and hard work can do.

 

[Keyfer 55]

Is 168 gr sierra soutible for 1000 yd. I never got a chance to shoot that far ??