6.5 PRC and RL-26

[Caseknife]

A little background; I've been reloading many different cartridges for over 35 years and never had this happen.

Finally got my hands on a couple pounds of RL-26 to try.  I have been using Quick Load for the last year to help determine loads using RL-16 and 17 in my 6.5 CM.  Not many manuals out there offering the data.  I will use the Propellant Table Setup chart to help determine charge weights with the most efficient powder, making sure to input the proper barrel length, loaded cartridge length etc.  I have always used the charge weight that is listed at the 10% below SAAMI pressure as my max.  My start load is usually 2 grains below that and my test loads work up in increments of .5 gr, 5 loads of 4 rds each.  This method has worked well in the past, luck?  Always watch signs of pressure, stiff bolt, ejector swipes, cratered primers, etc.  Yesterday I shot the loads that I had loaded with RL-26, starting load was 58.5 grs, CCI-200, Hornady neck sized cases, Barnes 127 LRX at 2.88".  QL had the load listed as 50,617psi, SAAMI is 64,991psi and a velocity of 3041fps.  So off I went, first shot, 3324fps with Labradar!!  Blown primer - first time ever, WOW, wtf?  Case head had expanded .0035", primer that was in the blind magazine just fell back in the case.

About put 2 pounds of RL-26 back on the market!  Definitely pulled all the bullets and started over by loading 4 rounds with 54 grs.  Much better results, but bolt was still a bit stiff opening, no case head expansion.  Seems that 53.7 is just about right, with speeds averaging 3175fps.  I have heard that RL-26 is magic, but 400 fps over what is listed for the powder charge isn't magic, its scary.  In order to hit the velocity that my first shot did, QL indicated that I would have charged it with 64 grs and hit a pressure of over 71K.  I know QL is for estimating purposes and not to use it as a direct replacement of reloading manuals, but what is a guy supposed to do when encountering new cartridges and powders?  Thought my method was foolproof, but now I am not so sure.

[Karl Blanchard]

I really gave RL26 an honest try but in 4 calibers I tried it in I did get slightly better speeds with less powder but pressure is pressure and at the end of the day I'm not gonna kill myself trying to locate a powder that's impossible to find just to gain 20fps. Not to mention it's not overly temp stable. If I were you I'd off it and move on with life.

As for your blown out brass, are you positive you threw the right powder charges? I've seen nothing from 26 that would make me believe it's that fast. I've yet to load for the prc so I couldn't speak to any of your numbers.

[Magnum_Willys]

Some powders QL is waaaaayyyyy off.   Like retumbo in some cartridges.   Not saying I wouldn’t have done the same.  Good reminder for me not to use QL to shortcut right up to near expected  node.   Ive been tempted.

[Karl Blanchard]

 I trust almost nothing. I'll take min book from nosler, hornady, or the like and start low.  Single rounds in half grain increments until I find my own data. Start low work high always. If it's a powder/chambering I have history I will short cut it but otherwise start low. I do load workups on A LOT of rifles every year and I've yet to pop a primer on the first shot 

[JeffRaines]

A little background; I've been reloading many different cartridges for over 35 years and never had this happen.

Finally got my hands on a couple pounds of RL-26 to try.  I have been using Quick Load for the last year to help determine loads using RL-16 and 17 in my 6.5 CM.  Not many manuals out there offering the data.  I will use the Propellant Table Setup chart to help determine charge weights with the most efficient powder, making sure to input the proper barrel length, loaded cartridge length etc.  I have always used the charge weight that is listed at the 10% below SAAMI pressure as my max.  My start load is usually 2 grains below that and my test loads work up in increments of .5 gr, 5 loads of 4 rds each.  This method has worked well in the past, luck?  Always watch signs of pressure, stiff bolt, ejector swipes, cratered primers, etc.  Yesterday I shot the loads that I had loaded with RL-26, starting load was 58.5 grs, CCI-200, Hornady neck sized cases, Barnes 127 LRX at 2.88".  QL had the load listed as 50,617psi, SAAMI is 64,991psi and a velocity of 3041fps.  So off I went, first shot, 3324fps with Labradar!!  Blown primer - first time ever, WOW, wtf?  Case head had expanded .0035", primer that was in the blind magazine just fell back in the case.

About put 2 pounds of RL-26 back on the market!  Definitely pulled all the bullets and started over by loading 4 rounds with 54 grs.  Much better results, but bolt was still a bit stiff opening, no case head expansion.  Seems that 53.7 is just about right, with speeds averaging 3175fps.  I have heard that RL-26 is magic, but 400 fps over what is listed for the powder charge isn't magic, its scary.  In order to hit the velocity that my first shot did, QL indicated that I would have charged it with 64 grs and hit a pressure of over 71K.  I know QL is for estimating purposes and not to use it as a direct replacement of reloading manuals, but what is a guy supposed to do when encountering new cartridges and powders?  Thought my method was foolproof, but now I am not so sure.

Just had something similar happen in 280ai with the same powder although I started much lower. QL was showing me 61 or 62gr max @ 2900 or so fps so I loaded from 56-62. Luckily I did because 56 was pushing 2800fps. 61 would've likely been a bad kaboom.

Start low, work up always. If you don't mind me asking, who made your rifle?

[Caseknife]

Thanks for the input guys.  I'm pretty anal and weigh all my rifle loads on a beam scale, double and triple checking what the scale says per each 4 rounds of the load weight, then do the same for the next 4 rounds, so I am confident on the charge weight that went into that round.  Had no issues with RL-25 in the same cartridge, but the issue with RL-26 through me for a loop.  Definitely will be starting much lower in the future.  Load Barnes ttsx or tsx exclusively and all start .050" off the lands, so that wasn't the issue.

The rifle is a spare Winchester 300WSM that I sent to Benchmark and they rebarreled it for me, very satisfied.

[mazama]

I looked that powder up in the burn rate chart it is between 7977and h100, max is 58-59 for those,you were close to max,but you should not have gotten anywhere near that velocity or pressure.I shoot barnes bullets in a 284win with a long throat,but I steped down to 120weight because of the length,if your bullets are seated deep,they will take up a lot more space than a lead copper will.

[JBar]

I'm using 26 in my PRC. 55.5 with a 140g AB getting 3030 fps from 26 inch barrel. Check Alliants website for load data. Shouldn't be to hard selling the 26 if you decide to m.j go.another direction.