Are there some barrels that are impossible to load develop for?

[Forum Boss]

ES 3-6 is possible, but extremely difficult, and probably not repeatable for four 5-shot groups in a row without extreme procedures and an exceptional barrel. The best F-Class shooters I know are achieving 10 or under ES for five shots, pretty regularly. This is with regular annealing, AutoTricklers, base-to-ogive sorted bullets, turned necks.

ES does not directly correlate to group size on target. However, consistently low ES is a darn good indicator that you are doing things RIGHT during the reloading process. This would include:

Very consistent powder charge
Bullet base to ogive held very consistent
Neck tension consistent, and neck chamfers smooth and consistent
Consistent seating pressure (now measurable with AMP press)
Good selection of primer for your powder and primer hole size

100-200 is a different game. No question some insanely good groups have been shot with high ES. However I have every confidence that ES over 20 will show up at 600 yards on target as a lower score and bigger group size. My 6BR loads for 600 ran around 11-12 fps ES. That was with Varget and CCI 450s and Scenar 105s.

Back to the OP -- If he wants to get the ES below 20 fps he needs to consider changing powder. But the issue is probably related to the barrel.

I wasted nearly two years trying to get a factory .260 Rem barrel to shoot. I finally replaced it with a 6mmBR PacNor. The first measured group out of that barrel, rounds 17-20 (4 shots), was a witnessed 0.168" at 100 yards. ES about 15-16 fps, if I recall. Switching to an arbor press and getting more carbon inside the necks lowered that to 11-12 fps and I was happy with that, as the gun had less than 2" of vertical at 600 yards (with low winds).

The eye-opening discovery of going from a 0.8-MOA .260 Rem with 20+ ES to a quarter-MOA 6BR with ES in low teens (with exact same action, stock, and trigger) was what inspired me to start this website way back in 2004, as 6mmBR.com .

 

[CamTheBam]

That isn't necessarily true. Nobody shoots smaller groups at 1000 yds than the discipline of long range benchrest. Period. We do not obsess over low ES. We obsess over group size.

More often than not, the smallest group doesn't have the smallest ES. Even when tuning at short range (200-300 yds), we never pick a load with a smaller ES over a load with a smaller group. Further, when we are shooting our tuning ladders at 1000 yds we often don't even bother to get out the chrono.

ES is simply an indicator. If it is under 20 fps it is fine, and under 30 fps is probably okay too. The goal is to have a tuning node where the bullets will impact at the same POI with a 20-30 FPS velocity spread. (We don't always get that wide if a node.) Now if the ES is 50 or 60--while it might shoot a good 100 yd group--it probably won't shoot a good long range group.

So there are some things ES can tell us. When I occasionally chrono my 1000 yd BR loads, they are usually in the single digits to low teens. This tells me my loading practices are solid. It tells me that things like weighing primers and seating them to an exact crush with a K&M Primer Gauge does make a positive difference.

If the ES is small but the group is big, then my loading practices are fine but the barrel hates that powder/bullet/seating combo.

If the ES is big but the group is small, it might be an indication of needing more neck tension. The theory here is that the bullet needs to be delayed a tiny bit more before it starts down the barrel to help the powder burn more uniformly.

I recently worked up a load for a customer rifle. It was a hunting rifle in 338 Lapua. The load I found produces a .4" 3-shot group at 100 yds and had an ES of 22. That was the best I could get this rifle to shoot.

The customer took it to a long range shooting course and hit every target out to 2600 yds. He said he still wasn't really happy with the load because it's ES was 22. I pointed out that if he was consistently making hits to 2600 yds then the ES was fine. Then I explained the whole deal with ES and he is now happy.

Interesting! Thank you!

 

[CamTheBam]

Thanks for the replies guys, lots for me to think about, here!

 

[chop house]

But my ES was 3fps. I just don't understand

add a tuner

 

[CamTheBam]

Yeaahhh 5 years is plenty of time, I would've moved on 4 years ago.

To be honest, it's just my sense of pride and my sheer bloody mindedness that has kept me going back to it... if I had any sense I would have chucked it in a long time ago!

 

[CamTheBam]

If it's hyper accurate, and it's only the ES (ie, velocity variances) that is the problem, then to me it would eliminate anything wrong with the barrel / rifle / scope. The ES would - IMHO - be related to ignition / combustion issues then. You already do the rest of the typical steps correct as far as I can see. Have you tried
a) different powder as suggested by another poster
b) different primer - possibly even playing with primer seating depth

So far I've tried H4350, RS62, RS60, N150, N550, N555, N160 and Federal GMM & CCI normal and BR2s... the attached photo is a 5 shot group on one of the small Shoot'N'C pasters @ 100 yds.

 

[Hohn]

It’s always important to know when the means to an end have become ends in themselves. I watch a lot of Mark and Sam after work and I’ve never seen Mark talk about ES in his loads and he’s shooting 3000y+ at times. If it doesn’t matter to him, it doesn’t matter for what I’m trying to do.
The fallacy underlying concern about ES is that each shot is leaving the barrel at exactly the same vertical so vertical variation due to speed is an issue. But if you’ve developed a load such that you slower loads are on a slightly higher trajectory, most of that can be canceled. Some people call this “positive compensation.”

 

[DaveTooley]

So far I've tried H4350, RS62, RS60, N150, N550, N555, N160 and Federal GMM & CCI normal and BR2s... the attached photo is a 5 shot group on one of the small Shoot'N'C pasters @ 100 yds.

And this is a problem? In all the years of shooting 1K BR I never once used a chrono to tune a rifle. The target tells all. The best 1k groups I ever shot were practicing for the nationals. Unsorted bullets and powder charges thrown from a powder measure at the range. When everything is right in the world you have to work hard to screw it up.

 

[piie]

So far I've tried H4350, RS62, RS60, N150, N550, N555, N160 and Federal GMM & CCI normal and BR2s... the attached photo is a 5 shot group on one of the small Shoot'N'C pasters @ 100 yds.

Perhaps it's incomplete burning of the powder?

Have you loaded your metrics into QL and check to see wrt case fill and burning % of powder?

As n "what the heck" check - try your best performing powder and play around with lower powder loads - ignore the target, just see if you CAN actually get lower ES in the first place. After that, I would say that you should just pack up that rubbish rifle barrel and mail it to me - I'll punish it for you

 

[Webster]

To be honest, it's just my sense of pride and my sheer bloody mindedness that has kept me going back to it... if I had any sense I would have chucked it in a long time ago!

The top short range bench rest shooters buy as many as 15 high quality barrels every year. Tony Boyer says he can tell if a barrel will shoot small with about 30 shots. They are trying to shoot aggregates under 0.0200". They toss the barrels after about 600-800 shots. Most of the top shooters at big matches are shooting Bartlein or Kreiger barrels. Who knows what the quality is on some of the other brands. I'm sure barrels like Hart and Shilen are good but you don't see them as much in competition. You need a very good barrel and the best bullets to be competitive, plus personal skills. I'm a GH hunter. Don't shoot competition. I can tell if a rifle will shot under 0.500" with very few shots down the barrel.

You still have not described your rifle and what it's used for.

 

[JEFFPPC]

Ok, I will say it again. A lot of guys would be better off without a chronograph and without a borescope. Yes, I have both. Yes for a short time I used both a lot. During that time my match performance went down hill. Now they gather dust and match results are pretty good. I know my idea of success , head to head competition, is not what everyone strives for, but we can all fall into the trap of getting lost in the details . I often read on here guys saying, trust the target. Good advice I have taken.

 

[Beiruty]

Yes, there are rifle built like stick and paste and who knows what barrel they used.
However some other semi-custom or fully custom rifle (Very heavy) can shoot 0.25 MOA from the first 5 shots and I have witnessed and recorded that fact.

 

[darkangel_r2]

So far I've tried H4350, RS62, RS60, N150, N550, N555, N160 and Federal GMM & CCI normal and BR2s... the attached photo is a 5 shot group on one of the small Shoot'N'C pasters @ 100 yds.

What chambering, bullet weight, and barrel length do you have? If you are running 4350 class powders barrels below 24" or so can have an incomplete burn with them.

If your barrel is short add some neck tension, throw a magnum primer in there, try jamming, go to a lighter bullet with a faster burning powder.

Whats the bore look like? inconsistent coppering or tooling marks can effect velocity stats and accuracy or only one at a time.

Whats your chronograph?

 

[Tommie]

About 40 shots total down this tube. Don’t believe I’ll be finding any load it likes.

 

[CNC-Dude]

Brian also mentions in an interview with the Ultimate Reloader on YouTube that they don't give medals for the lowest SD's or medals for the best groups, they give medals for the best score. The range master at the range I shoot at is also a long time competition shooter has said, " The lowest ES and SD dont always provide the best groups. So don't become blind to what the target is telling you, they don't lie!"

Think it was Brian Litz who won a Natl Championship with a rifle that was shooting SD's in the high 20"s , and ES all over the map . Last Thursday ; on a 600 yard practice at BA , I shot a 200 - 13x , and a 200 - 14x about a half hour apart . First string , SD was 19 , and second string , SD was 26 . But 200 is 200 . I can live with funny SD for 200's .

 

[gunsandgunsmithing]

About 40 shots total down this tube. Don’t believe I’ll be finding any load it likes.

The fouling doesn't bother me so much, but where's the throat? It might be an optical thing but it looks like the end of the neck has no transition..just straight to lands and grooves!

 

[Tommie]

The fouling doesn't bother me so much, but where's the throat? It might be an optical thing but it looks like the end of the neck has no transition..just straight to lands and grooves!

Optical illusion.

 

[gunsandgunsmithing]

Optical illusion.

Well, how's it shoot then? If it shoots good, jb that sucker, get it good and clean and shoot it. I've seen a lot worse fouling in guns that flat shoot! Is the fouling your concern? It looks a little rough but I'd jb it real good and see what it does. It may shoot just fine. If you don't like it, tell me where you throw it away. Lol!

 

[WayneShaw]

And this is a problem? In all the years of shooting 1K BR I never once used a chrono to tune a rifle. The target tells all. The best 1k groups I ever shot were practicing for the nationals. Unsorted bullets and powder charges thrown from a powder measure at the range. When everything is right in the world you have to work hard to screw it up.

This is the best advice one could ask for.

 

[B Nettesheim]

Until there is a match where the scores are determined on the lowest es I wouldn’t pay as much attention to the numbers but rather small round groups