Reloader 26/Short Barrels

[Monteria]

It sounds like you are comparing published max book data. That's far from conclusive and farther from a scientific experiment. Try pushing RL26 to actual max pressure in your rifle, and you will likely see a very different result.

 

[Exarcher]

25-50fps is what is expected (per inch) velocity loss.. so your 185fps loss is right there.. You've discovered some great information,, regarding the faster powder velocity.. Thanks for sharing this!

 

[VTbluegrass]

Sample size of one on the burn rates vs barrel length is not significant to draw a linear conclusion and make it say a rule of physics. If this were the case my 270 with a 22" barrel would be faster with 4350 or 4831 than it is with Reloder 23. But in my rifle the Reloder 23 smokes the other two by about 100fps.

 

[highfinblue]

Until today, I never put any stock into there being better powders for short barrels. I believed that if a listed powder was the fastest when tested in a 24 inch barrel, it would still be the quickest in a shorter tube compared to other powders.

This is not true.

I have been struggling to get velocity out of a 20 inch 300 WSM I just built. Rather than ramble, I'll give you the velocity numbers.

69 grains of reloader 26, 190 Speer Impact, is getting me 2,820 fps.

The load manual says 3,004 fps with a 24 inch barrel. I knew I would lose some velocity but not 184 fps!

So after 60 rounds of this, I finally just try a faster powder. 66.5 grains of Staball 6.5 got me 2,910 fps and less case expansion measured by a micrometer.

Hodgdons load manual says that 66.3 grains of Staball 6.5 should get me to 2,960 fps. in a 24 inch barrel with 61k psi.

So I pushed it a little past max due to a little bit of head room on the pressure and the cases are doing fine. The velocity loss from a 24 to a 20 inch tube isn't even worth mentioning.

Unless anyone with some experience here can give me a better explanation, I'm going with the faster burn rate was what made the difference.

I would be interested to see velo in a 24" tube with that load, and the crazy thing is it also would probably be different in every 24" tube you sent one down. Love StaBall 6.5, I run it in a CM and 22-250 and it is lights out with both rifles.

 

[meatyrem]

Sample size of one on the burn rates vs barrel length is not significant to draw a linear conclusion and make it say a rule of physics. If this were the case my 270 with a 22" barrel would be faster with 4350 or 4831 than it is with Reloder 23. But in my rifle the Reloder 23 smokes the other two by about 100fps.

Want to try R-23 with my 280 and see how it does

 

[meatyrem]

I would be interested to see velo in a 24" tube with that load, and the crazy thing is it also would probably be different in every 24" tube you sent one down. Love StaBall 6.5, I run it in a CM and 22-250 and it is lights out with both rifles.

Never thought of it in a 22-250. What weight you running with 22-250?

 

[highfinblue]

Never thought of it in a 22-250. What weight you running with 22-250?

I use 39 grains behind Hornady 68 grain bthp #2278, super accurate, haven't shot much besides paper, been a busy winter lol, but they are super accurate, right at 3300 fps. Don't use that as a starting load in your rifle, but it works in mine.

 

[Ga6570]

Makes sense.

What I have read or heard is that the actual burning of the powder is done relatively quickly with either a fast or slow powder, it's the expanding gasses, post burn, are what is accelerating the bullet further.

This burn rate in shorter barrels is a myth.

I don't believe that anymore. The faster burning powder was clearly better in my 20 inch barrel. What I could do is fire both loads in my 24.3 inch barreled 300 WSM and compare those. The reloader 26 should be slightly faster or at least comparable.

I'll try that and report back.

I'm interested in seeing the results if the two barrel lengths loaded with the same ammo and the associated velocities.

I like data.

 

[highfinblue]

I know a buddy of mine shoots a 28 Nosler with a 24" barrel, mine is 26", our loads are nearly identical if not the same, and velo is hardly different. I cannot recall off the top of my head the difference between the two, but he has no more problem banging steel at 1000 yards than I do, and on good days with little to no wind it is really not hard to do. We have both taken game at some extreme ranges, and I have not missed an animal I shot at, at those ranges. I am very particular with taking long range shots at game, when it is windy, I just don't shoot. I don't hunt with my buddy, he has permission where I don't and vice versa, so I cannot speak of him missing. I know he did miss a doe or two one day because his barrel was touching his side mirror. He was sitting in his truck in Kansas on private property watching a big chunk of ground trying to take does was why he was in the truck. The guy he hunts with is stricter than a game warden so nothing illegal was taking place. It was only after investigation he realized his barrel was touching his mirror, we both know better than that. I won't allow anything to touch my barrel when shooting, not even a finger, barrel harmonics are not voodoo, they're real. I should mention we both shoot suppressed, and I wish my barrel was 24" or shorter as well lol.

 

[Son of a Gun!]

Until today, I never put any stock into there being better powders for short barrels. I believed that if a listed powder was the fastest when tested in a 24 inch barrel, it would still be the quickest in a shorter tube compared to other powders.

This is not true.

I have been struggling to get velocity out of a 20 inch 300 WSM I just built. Rather than ramble, I'll give you the velocity numbers.

69 grains of reloader 26, 190 Speer Impact, is getting me 2,820 fps.

The load manual says 3,004 fps with a 24 inch barrel. I knew I would lose some velocity but not 184 fps!

So after 60 rounds of this, I finally just try a faster powder. 66.5 grains of Staball 6.5 got me 2,910 fps and less case expansion measured by a micrometer.

Hodgdons load manual says that 66.3 grains of Staball 6.5 should get me to 2,960 fps. in a 24 inch barrel with 61k psi.

So I pushed it a little past max due to a little bit of head room on the pressure and the cases are doing fine. The velocity loss from a 24 to a 20 inch tube isn't even worth mentioning.

Unless anyone with some experience here can give me a better explanation, I'm going with the faster burn rate was what made the difference.

I've always went by the 30-35 fps per inch rule and found that is usually pretty close!

 

[Buttermilk]

I shoot a lot of short barrels. I've been primarily a handgun hunter since 1993.

In most cases, the same powder that gives the fastest velocity in rifle barrels also gives the fastest velocity in shorter barrels. There are exceptions to this, but generally speaking, that's the rule.

I shoot or have shot several big cases such as 30 Nosler, 7 SAUM, 30-338WM, 7RM, 30-06 JDJ, 30-30AI, 280AI, all in short barrels, 14"-19" in length.

If you've ever seen a pressure trace of a round being fired, most traces show the powder is burned within the first 3 inches or so of barrel length. Longer barrels allow for more efficient use of the gas volume and thus higher velocity.

I'd say you have seen a pressure peak with SB6.5 that's higher than the pressure peak of RL26, and thus higher velocity.

 

[VinceMule]

Will, that is one heck of a shooter!

 

[highfinblue]

I shoot a lot of short barrels. I've been primarily a handgun hunter since 1993.

In most cases, the same powder that gives the fastest velocity in rifle barrels also gives the fastest velocity in shorter barrels. There are exceptions to this, but generally speaking, that's the rule.

I shoot or have shot several big cases such as 30 Nosler, 7 SAUM, 30-338WM, 7RM, 30-06 JDJ, 30-30AI, 280AI, all in short barrels, 14"-19" in length.

If you've ever seen a pressure trace of a round being fired, most traces show the powder is burned within the first 3 inches or so of barrel length. Longer barrels allow for more efficient use of the gas volume and thus higher velocity.

I'd say you have seen a pressure peak with SB6.5 that's higher than the pressure peak of RL26, and thus higher velocity.

There's so much amazing information, and technology that's available, and I just don't have time to research it all myself. This is why I so appreciate this group, there are some folks that have spent the time and I get to pick up the change. Thanks all. I'm definitely interested in shorter barrels for the simple reason I want to shoot everything suppressed. Way easier on my ears.

 

[AZ82New]

Ok, so I just took out the SAKO 85 that has a 24.3 inch Bartlein 2b. This rifle has roughly 200 rounds through the barrel whereas the 20 inch model 70 with the muller works cut rifle barrel had less than 100.

Velocity's:

RL 26: 3,089 fps with the 190 Speer Impact.

This was literally the same ammo I loaded up the day I shot it out of the 20 inch barrel at 2,810 fps.

Staball 6.5, 3,049 fps.

This was not loaded the same day but I loaded to the same specifications as before.

140 fps (Staball 6.5) difference makes sense out of 4.3 inches difference in barrel length and a different barrel that may be inherently faster and is fully broken in.

Nearly 300 fps (Reloader 26), doesn't make any sense other than that slower burning powder needs more barrel length to perform.

I did notice that I was getting heavy bolt lift in the reloader 26 load and slightly heavy in the Staball 6.5 load. I think im probably jamming the bullet in the SAKO whereas the model 70, cut with a different reamer, has a little more freebore . Also, it was drizzling. So there likely was some moisture on the cartridges that was increasing pressure.

Nonetheless, there was similar velocity and less pressure with the Staball 6.5 load. Also, what one would predict in difference in velocity with each given barrel length made more sense.