ever had a rifle qiut liking scenars?

[learjet]

ill try to keep it short...

i started usin 155 scenars in my m1a, it just felt the 175s were beatin her a bit. this was roughly 10 years ago...it shot them well, and continues to

built a bolt action 308 a few years back, and started w the scenars right away. it shot an honest everyday .6 moa for 1300 rounds. last fall i was shootin at paper, which i dont do often, and saw my groups were 1-1.5 moa. it was cold, i was tired, didnt make much of it. btw i shot groups to 500. messed w it all winter, and this spring, and the gun averaged 1.3 moa. over this many attempts i knew something was wrong. all these rounds were loaded last year in a batch of 500. also, this batch had shot well before the day i noticed i had issues. first i assumed gun/scope etc...checked the ez stuff, swapped scopes etc...no change

ran out of the 500rnd batch, loaded 100 more...

on a whim i bought a box of 20 175 FGMM....

next trip after reassembling the rifle the scenars shot 1.3ish, and the FGMM shot .4...i was impressed, had the same results w both loads, using 2 shooters.

time to examine my reloading equipment and practices...checked everything...even though ive been reloading for 35 years i had another experienced reloader go over my stuff and techniques...no problems found

went to the range again, scenars 1.3ish, my friends 175 load shot under .5. multiple groups and shooters again.

i bought some 175s, loaded them up, 44g varget, 2.800 and shot the best groups of my life on the 3rd try. scenars still 1.3ish...also my m1a still shoots the scenars just under 1moa, all ive ever asked of it. my sons 308 still shoots the scenars well

no real biggie...gonna use 175s for a while...

instructors at the LR class i took looked at me funny a few years back, said "scenars huh? theyll work till they dont"

anyone else seen this? more a curosity than anything, im sitiin on 2k of them, got 3 rifles (m1a, sons 308, and my 300wsm) that still shoot them well, but i am perplexed...

 

[thespecialist]

Re: ever had a rifle qiut liking scenars?

I may be wrong here, but aren't Scenars a little sensitive to their distance from the lands?

Have you checked the rifle to see if the bullets still have the same amount of jump as when you developed the load?

Not questioning your knowledge, just trying to help out.

 

[learjet]

Re: ever had a rifle qiut liking scenars?

hey np!

yep, used both a comparator set and my prec mic, throat appears not to have moved

 

[vman]

Re: ever had a rifle qiut liking scenars?

I was going to suggest throat errosion, but if you have checked that already then Im not sure.

They are harder to "get going" imo than the 175smk.

They have a sweet spot, or thats what I have found anyway.

 

[Skg_Mre_Lght]

Re: ever had a rifle qiut liking scenars?

I never could get them to shoot, at all, out of my Rem 700 SPS Varmint.

I bought 200 of them and played with them, and tweaked this and that, until I ran out, and I finally gave up.

I figured that if I am spending $.50 a bullet, I will just buy Bergers...something I can also hunt with.

In the interest of economy vs. performance, I settled on AMaxs (something I can also use reliably on animals), and since I am very isolated from any long range competition, I am not concerned about getting a couple of extra "x's".

 

[Leaddog]

Re: ever had a rifle qiut liking scenars?

The 155's were not designed for the rifles we normally shoot. They were designed for 1:13 twist 30" barrels that the Palma guys use.

Maybe you are lucky to find that they make you happy, but generally the heavier HPBT bullets with tangent ogives are the ticket.

I said goodbye to the 155's a long time ago.

 

[vonbalkenbush]

Re: ever had a rifle qiut liking scenars?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Leaddog</div><div class="ubbcode-body">The 155's were not designed for the rifles we normally shoot. They were designed for 1:13 twist 30" barrels that the Palma guys use.

Maybe you are lucky to find that they make you happy, but generally the heavier HPBT bullets with tangent ogives are the ticket.

I said goodbye to the 155's a long time ago.
</div></div>

I'm with LD on this one, the Scenar has a secant ogive, just like most of the Berger VLD's and is really not designed to be "jumped" into the lands of the rifling. You're better off with SMK's or the Berger BT Long Range bullets that are not secant ogive bullets.

-SBS

 

[mavrick10_2000]

Re: ever had a rifle qiut liking scenars?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: thespecialist</div><div class="ubbcode-body">I may be wrong here, but aren't Scenars a little sensitive to their distance from the lands?

Have you checked the rifle to see if the bullets still have the same amount of jump as when you developed the load?

Not questioning your knowledge, just trying to help out. </div></div>

Not sensitive at all. Scenars don't care if they're touching the lands or a good distance off. That's from a TRG22 and a factory Remmy sewer pipe.

 

[Michaelvoigt1]

Re: ever had a rifle qiut liking scenars?

I would be sure there is a smooth throat in the barrel.

A work over with JB compound has worked for some.

I use the Throat Maintenance bullets from Dave Tubb - they can often make a startling difference in the situation you are referring to.

The Sierra bullets are certainly more forgiving than the Scenars, but performance take some tuning.

 

[gvanhyning]

Re: ever had a rifle qiut liking scenars?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SagebrushShooter</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Leaddog</div><div class="ubbcode-body">The 155's were not designed for the rifles we normally shoot. They were designed for 1:13 twist 30" barrels that the Palma guys use.

Maybe you are lucky to find that they make you happy, but generally the heavier HPBT bullets with tangent ogives are the ticket.

I said goodbye to the 155's a long time ago.
</div></div>

I'm with LD on this one, the Scenar has a secant ogive, just like most of the Berger VLD's and is really not designed to be "jumped" into the lands of the rifling. You're better off with SMK's or the Berger BT Long Range bullets that are not secant ogive bullets.

-SBS </div></div>
-1 ... I disagree. I have two Remington action .308's, one a custom build and the backup is a GAP Rock. Both have Rock 5R barrels, the custom is 24" and the GAP is 22". Both shoot the 155 Scenars sub MOA. I don't believe guns stop liking bullets either so I'm inclined to believe it's possibly powder lot difference or maybe bullet lot. I have found that I need to check the C.O.A.L. with a new lot of bullets and adjust the seating depth accordingly. Have you shot any rounds since the change through a chronograph? There are some velocity influenced sweet spots. For the record, I do shoot some 175 SMK's too, just not as many.

 

[kill_goose]

Re: ever had a rifle qiut liking scenars?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mavrick10_2000</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: thespecialist</div><div class="ubbcode-body">I may be wrong here, but aren't Scenars a little sensitive to their distance from the lands?

Have you checked the rifle to see if the bullets still have the same amount of jump as when you developed the load?

Not questioning your knowledge, just trying to help out. </div></div>

Not sensitive at all. Scenars don't care if they're touching the lands or a good distance off. That's from a TRG22 and a factory Remmy sewer pipe. </div></div>

That has been my knowledge and experience with them in half a dozen or so factory guns as well.

Pretty forgiving to load for, dont mind a jump, and shoot well.

 

[learjet]

Re: ever had a rifle qiut liking scenars?

same lot of powder and bullets, heck same brass and primer lot as well hehe...nothins changed component wise. i was in the middle of a 500 round batch when i noticed it had opened up. the barrels a 26" 10 twist mcgowen w 1300 rounds through it, nearly all scenars @ 2940 w 46.5 varget, .040 jump. 6 sets of chrony data (5 or more shots) for this lot, over temps from 30-90 es 30 over all 6 strings, sd betw 9 and 14 for each individual string.

my m1a load jumps about .050, my sons stock 10FP jumps .040 as well.

just strange, in the middle of a 500 rnd lot of bullets my rifle decided it plain dont like them anymore.

 

[rcamuglia]

Re: ever had a rifle qiut liking scenars?

I think you need to check throat erosion again.

Every rifle will have some erosion in as little at 100 rounds depending on the intensity of the chambering. It is a good practice to check for erosion every 100 rounds.

You will have to make periodic changes in seating depth (closer to the rifling) as erosion occurs to keep accuracy acceptable.

If you have made no adjustments whatsoever in 1600 rounds, I guarantee that's the issue.

One thing about the 155 Scenar that a buddy of mine who shoots them just noticed. Lapua has changed the shape of the ogive. It is easily noticable just by comparing the two bullets from different boxes visually. No measuring with a comparator is necessary to see this. We called and emailed Lapua and got a response from a gentleman here in the USA. He says they have not changed anything, but some variation is possible as the moulds are changed. He asked for, and my buddy sent to him 3 of each bullet for inspection.

The newer bullet has more of a secant ogive than the older one.

Have you changed or bought new Scenars lately?

 

[learjet]

Re: ever had a rifle qiut liking scenars?

nope, still havent opened my last 2 boxes. bought 2k awhile back and was workin through them. im guessin its throat related as well, im limited by the length of my mag, so if i want a repeater i cant hangem out any farther. guess i could try seating them longer outta curiosity, but then im a single shot. i dunnno...thx!

for grins i opened my new batch of 2k...quick check shows no real difference in length or shape. base to ogive measures the same as the older bunch. gotem from PV, and these didnt come in factory lapua boxes, so i dont have a lot #

 

[bm11]

Re: ever had a rifle qiut liking scenars?

I have been having issues too. But it happened when I switched powder lots. I'm hoping it isn't the powder lot, I bought 24 pounds. I gave the barrel a thorough cleaning, in case it was coppering.

 

[vman]

Re: ever had a rifle qiut liking scenars?

bm11 did you clean and then find it turned to crap, or did it turn to crap and then you cleaned.

I find cleaning ruins my rifles zen and it takes a bit down the tube to get everything back to how it was.

 

[bm11]

Re: ever had a rifle qiut liking scenars?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: vman</div><div class="ubbcode-body">bm11 did you clean and then find it turned to crap, or did it turn to crap and then you cleaned.

I find cleaning ruins my rifles zen and it takes a bit down the tube to get everything back to how it was. </div></div>Turned to crap, then cleaned.

The barrel has 3200 rounds on it now, and I have only cleaned it sporadically. I did a load workup when I got this barrel back from the smith, and all loads tested were sub .5 moa using Scenars and Varget.

After I changed powder lots, I re did a workup, but all loads tested were now in the .75 moa to .9 moa range.

Here are a few variables it could be, I am trying to narrow it down to determine what I need to change to restore my accuracy:

1- The powder lot is different. It is a bit slower than the last lot, hence the new load workup.

2- The brass (Lapua) now has 5 firings on it. When I started this load workup, it was new or 1x fired. It hasn't been annealed, so it could be a neck tension issue, though my seating pressure feels uniform, and I have had some brass in the past where I could actually FEEL un-uniform seating pressure.

3- The barrel has 3200 rounds on it, perhaps there is enough coppering to have thrown off the accuracy.

I gave it a deep cleaning to eliminate variable number one. Next time I go to the range, I will try some new Lapua brass to see if it is the brass.

The only thing left at that point would be the powder, but I don't see that as being a real possibility. While it might require a different amount of powder to shoot, I shouldn't have an issue finding that amount.

To clarify- I can't say that it was precisely when I changed powder that the gun stopped shooting. The last few hundred rounds were shooting steel at distance up to 950 yards. At that point, my wind reading is not nearly good enough to tell the difference between a .5 moa load and a .75 moa load. It only became apparent when I went back to 100 yards for load development.

Finally- it is not that I experienced throat erosion. After giving the rifle a thorough cleaning, I remeasured the distance to the lands, and found they haven't moved.

Suggestions?

-Bob

 

[FCS]

Re: ever had a rifle qiut liking scenars?

While it is an apples to orange comparison, I had a similar issue with a 243 AI. Did a check and while the throat didn't appear to move the groups just wouldn't snug up no matter what I tried. Borescope revealed a good 6" of firecracked rifling from throat forward. Since barrel was 28" long and on a R700 I was able to hack off 6" and turn this barrel into an AR-10 barrel. Accuracy returned to what I expected.

If you've adjusted your charge of powder with new lot # for same velocity as old lot#, tried new brass, etc.....sounds like it is time for a new barrel to me or at least a peak with a bore scope to see what is going on.

Let me add that if bore looks horrible but groups are still tight I'm gonna keep shooting that barrel. However, if groups are not so great and first 6" of barrel looks like a dried up mud puddle I'll have a new barrel put on.

 

[bm11]

Re: ever had a rifle qiut liking scenars?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: FCS</div><div class="ubbcode-body">While it is an apples to orange comparison, I had a similar issue with a 243 AI. Did a check and while the throat didn't appear to move the groups just wouldn't snug up no matter what I tried. Borescope revealed a good 6" of firecracked rifling from throat forward. Since barrel was 28" long and on a R700 I was able to hack off 6" and turn this barrel into an AR-10 barrel. Accuracy returned to what I expected.

If you've adjusted your charge of powder with new lot # for same velocity as old lot#, tried new brass, etc.....sounds like it is time for a new barrel to me or at least a peak with a bore scope to see what is going on.

Let me add that if bore looks horrible but groups are still tight I'm gonna keep shooting that barrel. However, if groups are not so great and first 6" of barrel looks like a dried up mud puddle I'll have a new barrel put on.

</div></div>Had the bore scoped 766 rounds ago while it was at the smith for a chop and recrown (not rechambered.) He said that the throat was showing some fire checking and coppering.

I have a spare barrel (two really) if I need to, but this one only has 3200 rounds of .308 through it, so I doubt it's smoked yet.

 

[FCS]

Re: ever had a rifle qiut liking scenars?

Not uncommon for Palma shooters to set back barrel at 3500, put barrel on order, shoot another 500ish rds, and swap out barrel.

YMMV but if you saw firecracking 766 rds back, groups opening up, and tweaking load hasn't helped......

 

[bm11]

Re: ever had a rifle qiut liking scenars?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: FCS</div><div class="ubbcode-body">
YMMV but if you saw firecracking 766 rds back, groups opening up, and tweaking load hasn't helped...... </div></div>I hear ya. Again- I haven't shot it yet since a thorough cleaning, so that may be it, BUT if it doesn't clear up, I'll throw one of my other barrels on it.

I guess I just expected 8,000-10,000 rounds through it, after how many times I read that on here.

 

[MitchAlsup]

Re: ever had a rifle qiut liking scenars?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mavrick10_2000</div><div class="ubbcode-body">Not sensitive at all. Scenars don't care if they're touching the lands or a good distance off.</div></div>

A couple years ago when I did my load-development for the 155 Scenar, I noticed they liked short jumps (0.005 through 0.030) disliked medium jumps (from 0.035 through 0.075) and then went back to don't care (magazine length with a 0.120 jump).

I took this to mean that they are not particularly jump sensitive, but maybe they are sensitive to not wanting a medium sized jump.