Reloder 26 in 280 Ackley

[Ridgerunner665]

Messed around with some temp sensitivity testing today...I was testing Norma MRP...it failed miserably at 2.9 fps per degree...so I went straight to the fun store and got some Reloder 26.

61 grains of RL26 under a 160 Accubond....3,017 fps
ES....34
SD....17


10 rounds


That's the warm weather max... Now if it holds true to what Alliant says, and only loses .5 fps/degree....I'll be flying.


May try magnum primers to lower ES...


Reloder 26 isn't anywhere near as slow burning as QuickLoad says it is...in rounds comparable to 280 Ackley capacity, it is REALLY close to RL22 and MRP....Really close....Something else I noticed, when using RL26... The barrel gets warmer at the muzzle end than it does at the chamber end.... much warmer.


That said... RL26 is a cooler burning powder than MRP/RL22...Takes at least 2 rounds to get the barrel warm enough to feel it.



Burn rate (Ba) adjustment in QuickLoad is .386

 

[Ridgerunner665]

I debated between RL26 and IMR7977, they had both at the store...but I was afraid 7977 might be a little too slow for 160's...

I knew from some reports on Nosler forum that RL26 wasn't as slow burning as advertised in '06 based rounds, but didn't expect it to mirror MRP/RL22 so closely...in all honesty thats not a bad thing, 61 grains fits just fine with no compression (Redding Competition seater die)

 

[jrsolocam]

In the smaller to medium case capacity rounds with medium to heavy for caliber bullets the RD 26TH shines. I did a one half grain at a time elevator test with MRP vs RL26 with 105 A max in my new 240 Weatherby and got 100 fps more with R26 before pressure....

 

[Jokostel]

I haven't tried RL26 yet in my 280 AI, however, I have run I7977 with the 171 Barnes Match Burner and the 180 VLD hunting. Both shot ~2850fps with 60Gr of it and a 215.

 

[venatic]

I loaded 4 rounds in my 280 Rem(not AI) and with a 168gr Berger the Magneto said 2936fps with the highest load. No excessive pressure I could see.
1.5 inch group at 200'

 

[Jokostel]

Better than moa, but still not impressive...
A standard 280 Rem shouldn't be pushing a 160 any faster than 28-2850, hell, most good factory load are barely doing 2880 with 150s... Granted, the pressures are lower for the older pump/autoloaders....
Regardless, your pushing AI territory... Just watch if/when you change variables.gun)

 

[Lefty7mmstw]

Better than moa, but still not impressive...
A standard 280 Rem shouldn't be pushing a 160 any faster than 28-2850, hell, most good factory load are barely doing 2880 with 150s... Granted, the pressures are lower for the older pump/autoloaders....
Regardless, your pushing AI territory... Just watch if/when you change variables.gun)

it's a berger in his 280... gotta fiddle the barrel life away to get great accuracy with them in a lot of rifles.... stuffing the snot out of the rifle instead of using a bigger chambering likely isn't helping him either.
He could shoot a 7rum and shoot the 180 grain hpbt's at 3100 fps at start loads though.... my 7rum does 3080fps with 180 sierra's and I have all kinds of headroom...

heck, I've got a cream puff load for my 7rum with the 186 berger using rl50 that runs 2850 fps and the pressure is so low it barely seals the necks... The rifle would shoot forever using that load... I should turn that one up to see how fast that little bullet will go...
Come to think of it, I really haven't pushed the rifle though to see where it can actually go; I guess I simply do not care as it is enough already.
You don't floor your Ferrari just because; you only do it when you need to... You DO floor your 4 banger hatch all the time though; you are road pizza on a lane merge if you don't...

 

[Ridgerunner665]

More temperature testing...with my new MagnetoSpeed, I have confirmed that 61 grains of RL26 is the safe warm weather max with the 160 Accubond...I shot through both chrono's, just to see how the old ProChrono Digital stacked up against the MagnetoSpeed....the conditions are, its HOT...94 degrees.

The results are below...and also confirms that for ~$100, the ProChrono isn't a bad chrono at all...not perfect, but usable for the average Joe, if properly setup in the shade.

MagnetoSpeed
3,019
3,022
3,017
3,023
3,018

Average = 3,020, ES = 6, SD = 3
-----------------------------------------------------------------------

ProChrono Digital...15 feet from the muzzle
3,003
3,016
3,003
3,003
3,003

Average = 3,005, ES = 13, SD = 5

EDITED TO ADD: 24" barrel, Nosler M48 Custom rifle, 9 twist, stainless

 

[yawn]

It would be help full if barrel lengths are quoted alongside velocities.

 

[Ridgerunner665]

Something worth noting...even if it is a little off topic .

I'm also testing Norma MRP powder in (2) 270's..my wife's and my hunting buddy's...

MRP only went up 1 fps/degree in both 270's with 140 grain bullets...tested at 66 and 94 degrees.

There is some proof in your pudding that just because a powder does or does not work in one particular round...that doesn't mean it won't perform downright AWESOME in others.

Good thing too, I have 6 lbs. of MRP...

 

[Ridgerunner665]

It would be help full if barrel lengths are quoted alongside velocities.

Fixed...and thanks for pointing it out.

 

[Ridgerunner665]

On the mention of the 280 Remington...if its in a modern bolt action, you can run it up to 65,000 psi just as you can a 270 Winchester...

With the right powders, a standard 280 Remington with a 24" barrel can safely run a 168 grain bullet a little over 2,900 fps...and a 160 grain bullet up to ALMOST 3,000 fps (about 2,985 or so)...BUT, this does depend on the barrel...some will do this easily, others won't do it at all.

The Ackley only really gets you about another 50 fps over what a fully loaded 280 Rem can do...the real benefit of the Ackley is the greatly improved brass life.

With a 280 Ackley, you can get a little better than factory 7mm Rem Mag ballistics without destroying the brass on the first firing.

Running a 280 Rem at 63-65,000 psi can be safely done in a good bolt action, and that'll get you within 30-50 fps or so of anything an Ackley can do...but brass won't last long at those pressures.

All that said...the 280 Ackley loads I fired above (61 grains RL 26, 160 AB) are leaning on the brass pretty doggone hard too (63,000 psi)...but its 94 degrees out there...most of my shooting will be during the fall and winter, and that load will drop down around 58,500 psi in the cooler temps....all I was doing here was finding the MAX safe load that was good for any time of the year, if not for that...I wouldn't be shooting when its 94 degrees.


Coincidentally...in the cooler temps...the load should drop right into node 5.

 

[Lefty7mmstw]

this aint my first rodeo.... there is NO substitute for displacement when pushing bullets fast... I don't like to work my rifles that hard.... most people just judging there rifle's top performance based on brass signs overload their rifles... I'd rather stay back a good bit with a case that's actually rather big for the performance... things last better that way...

The last rifle I worked with a pressure trace on was capable of 75 kpsi with easy extraction ( a sendero in 7mm stw)... the top speeds in the reloading books are generally correct, if not actually optimistic for a given cartridge.... play hard if you want to; but don't make believe you aren't working the heck out of your rifle...
as to saami max pressures... if you don't have a pressure gauge on your rifle it's at best campfire talk as you don't have a clue where you actually are

 

[Jokostel]

Theyre all pressure engines..... theres no replacement for displacement.
I enjoy my 280 Ackley loafing at 3250. I've nipped the heels of 3400 on ä 140... each is of its own law... however, what your trying to pull is grossly over pressure forva standard 280. I should know.... I've only had five of them...