• Winner! Quick Shot Challenge: What’s the dumbest shooting myth you’ve heard?

    View thread

155grn Senars

Runamuk

Sergeant
Full Member
Minuteman
Sep 30, 2009
239
4
58
Southern IN
I’m currently shooting a Remy Custom shop 308 with a 20” barrel 1 in 12 twist that’s giving me fits with load development. I’m attempting to load the 155grn Senars over Varget to shoot up to 1000yds. I’ve gotten this load to shoot right at 1/2 MOA or better repeatedly at 100yds, but anything over that and the groups start to open up. At 200yds I’m getting 1 MOA (best groups), up to 2 to 2 ½ MOA. I’m starting to wonder if the 155’s need a faster twist due to their length? Also it hasn’t really mattered at the range I’m shooting them beyond 100yds. I’ve taken them out to 500 and my groups stay around 1 ½ to 2 MOA. I’ve ruled out the easy/common problems such as shooter error, equipment problems etc… I’m wondering if anyone else has seen this type of issue (shoots great at 100yds, terrible anywhere else). I’m thinking it might be time to try a different bullet, maybe the 155grn Sierra Palma bullets. For what it’s worth I’m currently loading them at .010 off, with 46.6grn Varget using Winchester brass and CCI Br2 primers @ 2816fps.
 
Re: 155grn Senars

Suggest you do some load development, look in load section 2816 fps is slow. Alot has been written in threads about 155 L in 20" barrels. In my 22" barrel over 2900 fps 8.4 mils at 1000 yds 3.4 mil at 600 yd about 3" vertical at 600 yds.

I like OCW load development method others like ladder test
 
Re: 155grn Senars

20" barrel should show pressure signs(cases) at 2900fps. you may not be able to shoots safe loads at that velocity. also you don't need to go with a faster twist on your barrel. i'm not going to say a 1 in 12 wont shoot 155s well, but a 1 in 13 might be a little better. groups tend to settle down at around 300 yards, you should test for loads and groups at that range if available. but 1/2 groups at 100 should not disappoint you.
I shoot a 29" barrel(palma rifle) and my safe load is around 2950. Ive seen guys try for 3000 but they are not safe in my rifle. I shoot 46.4 of varget with 155s. guys on the teams shoot as high as 47.5 of varget depending on lot#. be careful Ive got 9 inches on you in barrel length and we near the same velocity.

arborpro
 
Re: 155grn Senars

I have not been able to get the 155 Lapua or Sierra (both old and new) to shoot out of my 20" 1-12. I have talked to several other people who shoot the SPS tactical and hey can't get the 155 to shoot. I just went with the 175 and forgot about the 155.
 
Re: 155grn Senars

2950+ is even better. My AIAW 308 is 1:12" twist, and it stabilizes that 155 scenars just fine out to 1400 yards. (Not that I recommend shooting that far with a 308, but it was fun.) The scenar can be a very accurate projo, but you may have to play with the OAL a bit. As far as the 1:12" twist, it should be fine.
 
Re: 155grn Senars

Why are you trying to make a 20" 308 into a palma gun? I would try a milder load or switch to a heavier bullet like the 175smk. 308=/=300 win mag.

edit: 175 nosler, 178 amax, 185 scenar, 190 smk, so many good heavier bullets out there that will do what you want with 42-44 grains behind them. Why put a ton of powder behind a 155 out of a 20"?
 
Re: 155grn Senars

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DesertHK</div><div class="ubbcode-body">2950+ is even better. My AIAW 308 is 1:12" twist, and it stabilizes that 155 scenars just fine out to 1400 yards. (Not that I recommend shooting that far with a 308, but it was fun.) The scenar can be a very accurate projo, but you may have to play with the OAL a bit. As far as the 1:12" twist, it should be fine. </div></div>

Spot On...might be a bit tough to get that kind speed with a 20" bbl.
 
Re: 155grn Senars

If the guy is getting 1/2" groups at 100 yds the bullet is not the problem. I do not think a twist rate problem would show up by 200 yds(or even 500yds for an avg shooter) if he's at 1/2 moa at 100. Many have used the 155 in a shorter gun to good effect. My sources have done extensive testing on 175s vs 155s out to 1000+ yds. Reports are that better results are generally achievable from the 155s. Best results are generally achieved with a higher velocity node, but fast as you can go without welding your bolt or blowing your gun/self up may be a necessary trade off if you don't want/have a longer barrel. What is a chrony giving you for SD / ES? If no data you need to find a friend with one.
 
Re: 155grn Senars

Scenar shoots best when kissing the lands and reaching speeds of 2900FPS or more.

If you cant get that kind of speed due to a short barrel, try the 175smk.

The scenar is a fantastic bullet but its purpose is for palma shooting... and palma shooters dont run 20" barrels last i checked
 
Re: 155grn Senars

Yea re do your load develupments and group them at 300 yards.. sometimes the 100 yarder has a fluke and after 100 yards the load is crap.

If your not getting anything good move to 175's like vman said above.

If thats not working for you either your loads are sh** or something isnt right with you or that rifle.
 
Re: 155grn Senars

Most palma shooters run 28-30" barrels as much for the extended sight radius as for the velocity increases. They run 1:13" twist rates optimized for the 155's and it is not uncommon to see 3,000+ fps from 155's out of a long, tight bored (.3065") Palma barrel. Most serious Palma shooters optimize their equipment and practice around the 155's as they are required to use 155's for international competition. Note: when they can, some shooters at the regional Palma matches will use heavier bullets (190's) as it is believed heavier bullets tend to buck the wind better beyond 700 yards.

If you are getting 1/2 MOA at 100 then you should theoretically get 5" groups at 1000. Alas, this never happens in practice as a lot goes on the farther out you shoot. Psychologically it is much harder to shoot good groups at 2 and 300 yards than at 100. If your groups are holding 1/2 MOA vertically at 200 then you may be OK, otherwise try the 175's.
 
Re: 155grn Senars

I am going to be trying the Scenars out of my gun with a new powder by alliant, 2000mr. supposed to keep pressures down but get much higher velocities. we will see how it goes. if it shoots worth anything ill post back
 
Re: 155grn Senars

I got the best groups of any bullet I tried out of my Rem LTR 20" with 155 L scenar, 46.6 Vgt. Slightly under Half inch at 100. Problem I have with them is in the 4-500 range, they seem erratic here for me. Could just be me, but I don't get this issue with heavier bullets. Still working on this issue.
 
Re: 155grn Senars

Seaaggie if you are off Sunday there is a match 1000 yds at Bayou Rifles you can see my DTA SRS 22" barrel run 155 L IMR 8208 xbr 2900+ might be able to shoot some rounds for yourself.
 
Re: 155grn Senars

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Runamuk</div><div class="ubbcode-body">I’m currently shooting a Remy Custom shop 308 with a 20” barrel 1 in 12 twist <snip> I’m thinking it might be time to try a different bullet, maybe the 155grn Sierra Palma bullets. For what it’s worth I’m currently loading them at .010 off, with 46.6grn Varget using Winchester brass and CCI Br2 primers @ 2816fps. </div></div>

I shoot the 155 Scenars, the old 155 SMK (2155) and the new 155 SMK (2156) They all shoot well in my gun with a 1:12 twist 24" barrel.

However, you have to get thm up to 47.8gr Varget to make them shoot really well (47.5 gr in Lapua cases). Use a light primer (like CCI) and seat them long with 0.002 neck tension. 2816fps is just way too slow.

You can also get the Scenars to shoot at a lighter load, down near 43.6 gr Varget for short range stuff.
 
Re: 155grn Senars

Really stupid question that's probably already been accounted for, but it occurs to me to wonder...are your targets and aiming points the same size in angular units at each distance? I can see that someone who's shooting at the same hypothetical 1" target at 100, 200, 300 etc having issues due to being unable to properly see and align the reticle on the target.
 
Re: 155grn Senars

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: vman</div><div class="ubbcode-body">47.8 grains of varget! Is that on the verge of falling out of the case neck or what? </div></div>

I shoot 48 grains of Varget with mine. It's definitely a big crunch when I seat the bullets.
 
Re: 155grn Senars

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: vman</div><div class="ubbcode-body">47.8 grains of varget! Is that on the verge of falling out of the case neck or what? </div></div>

Its about 1/2 way up the neck, and is a compressed load. But after 1200 rounds, I still see no pressure signs.
 
Re: 155grn Senars

I use 47 grains of varget in my 308 (PGW Coyote) 10 twist 24" Kreiger using 155 scenars seated to 2.8 coal.

Getting to 2850 fps. Extremely accurate load with no pressure issues.
 
Re: 155grn Senars

ok, just got back from the range. my gun likes this new combo. Lake city brass, cci lr primer, alliant 2000mr (50.5 grs), 155 scenar seated to 2.900. no pressure signs even up to. I did how ever notice that my groups at 50.5 grs were best of the bunch. i did not have a chronograph, but i did figure out by working a ballistic calculation backward that it is going between 2820-2850. so even with my varget load, but without the pressure sign.
my grouping on this load was 1.7" at 400 yards. so it looks like i am going to stick to the 50.5 grs, and adjust my seating depth (just a hair too long to feed from the magazine) to see if that helps matters further.
 
Re: 155grn Senars

Hi,

Give H4895 a try with the 155 Scenars. Years ago I found out that H4895 will get me more velocity with less powder than Varget. 44gr of H4895, CCI BR2, Lapua brass will get me right around 2900 fps out of a 26 inch Mike Rock barrel. I can safely go above 44gr (46 is the max according to Hodgdon)but I'm trying to avoid compressed loads as I've noticed you get a lot more seating depth variation with compressed loads.

I recently purchased a Remington 700 LTR with a 20" barrel. I'm going to shoot 175 SMKs out of that. If you go to the JBM ballistics site and look at the Miller stability calculator you'll see that you can marginally stabilize the 155 scenar with the velocities you'll get out of a 20" 12 twist tube. Remington should have put a faster twist on that 20" barrel. The 175 SMK has quite a bit of margin. The 700 LTR is not a 1000 yard gun.
 
Re: 155grn Senars

What does the vertical spread look like at 500 yards? I'd put money on inconsistant velocities being the culprit. I had the same problem with Varget in a .308. 1/2 MOA at 100, and about 2moa at 600. After chronoing the load, I saw that I was getting an extreme spread of 50fps.

I get a much smaller ES with IMR 4350 which is kind of a slow powder for a .308, but I can't argue with results.

The Varget shoots much better at 300 and less though. Any farter and the ES starts to cause some vertical stringing. Hopefully, I can find a way to lower the ES and get the best of both worlds.
 
Re: 155grn Senars

It took me awhile to "tune" my scenar load. 47gr @ approx 2.85 produces 2915fps from my 24" Lilja. ES 15 for 20 shots and vertical 6cm @ 500m. 47.8 produced ave fps of 2937 and ES of 10 but I was starting to see pressure signs. So far I have 7 firings from the brass using the 47gr load and the brass still appears fine.
 
Re: 155grn Senars

Biggest thing I found was seating depth believe it or not. Was getting way too many fliers happening with the larger jump.

Kissing the lands has allowed me to get holes touching out to 400 yards provided I do my part and the wind is good.
 
Re: 155grn Senars

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: wisam</div><div class="ubbcode-body">What does the vertical spread look like at 500 yards? I'd put money on inconsistant velocities being the culprit. I had the same problem with Varget in a .308. 1/2 MOA at 100, and about 2moa at 600. After chronoing the load, I saw that I was getting an extreme spread of 50fps.

I get a much smaller ES with IMR 4350 which is kind of a slow powder for a .308, but I can't argue with results.

The Varget shoots much better at 300 and less though. Any farter and the ES starts to cause some vertical stringing. Hopefully, I can find a way to lower the ES and get the best of both worlds. </div></div>

at the load i had with 2000mr, it strung about one inch at 400 yards
 
Re: 155grn Senars

If you run out of patience with varget ,try Imr xbr 8208. You should reach 2850 fps safely for the 155s to perform out to 1k with your 20" barrel.
 
Re: 155grn Senars

I run 45.0 of RG4895 (very, very similar to IMR 4895) and 155 Scenars out of a 20" Rock, suppressed. We re-chrono'd the load again yesterday, and I hover at 2850 with an ES of 15 fps. Good accuracy to 600.

I have some IMR 8208 and the new Sierra 155 Palma bullets coming in, and I am hoping to get 2900fps accurately with the combination.