Was looking at Powder Valley and laughing at all the products that were listed as OUT OF STOCK,
when I noticed a new powder ( and I'm not sure what they were thinking when number this one) RL 15.5

Here is load data posted on it....https://www.powdervalleyinc.com/wp-content/uploads/2021/06/rlts155loadv2.pdf

Here is what was posted on their web site about it:

Alliant Reloder TS 15.5 Smokeless Powder
For consistent ammunition, choose Alliant Reloder 15.5 smokeless powder from Powder Valley. This medium rifle powder is temperature insensitive and highly reliable.

New intermediate burn speed between Reloder 15 and Reloder 16
World-class temperature stability
Ideal for loading heavy bullets in 308 Win and 223 Rem
Enhanced velocity in 6mm Wildcats versus Reloder 15
Contains decoppering agent
Load Data Here: Reloder TS 15.5

Probably not a good time to release it, but then who would have thought Biden would win.... even by Cheating...

always good to have another horse in the stable...If I ever see it, I'll look forward to trying it out... If I live that long, who knows how long we are going to have Clueless Joe and then Commie Harris in the White House... ( side thought, If Commie Harris ends up as President, with Joe Stepping down, are they going to change the name of the White House to the Whore House?? just a thought)

democRATS suck....

Sounds like it may be an excellent choice for 250 grain bullets in the 35 Whelen

Looks like a very useful powder. I'm sure I'll grab some if I ever see it.

Heard about it around 6 months ago and it sounded like a great powder. I hope to get some.

What does whoever is in the white house have to do with gun powder burning rates?

R15.5 looks like 15 and 16 had babies. Sounds perfect for the 375 H&H where 15 excels but is not very temperature stable. I have been getting good results with R-16 and use that anywhere R17 worked before. If I see this with out hazmat shipping fees I will definitely try some.

My thoughts exactly.

you two guys must be democRats and have no idea what being facetious is all about.....

sorry to make you two guys confused....

Have you been living under a rock?

Whenever I can get a pound I would to try it in my .22/250 and .22/6mm.

I want to run this in my Sako .338 WM Carbine...and my .308!...and .17 rem with 30gr. Bergers!

Way to go let’s introduce a new powder when we can’t even produce the ones we already have !

I get excited seeing any powder on the shelves, would be absolutely shocked to see a new one.

The alliant temp-stabilized double base powders are some of the best ever made - RL16, RL23, and AR-COMP. This joins that family. However it's so close to RL16 it's hard to get too excited.

They should have done a slow magnum temp stabilized version of RL33 instead.

I made some home brewed RL 15.5...

small batch.... 50% RL 15 mixed with 50% RL 16..... enough for like 10 rounds...

it went Bang, like any other powder....

I was both surprised and proud of myself...

now I can move on with my life, and still look at the empty shelves at my local Bi Mart...

but the knitting section of the store is still well stocked, and so was the paint section...

life is still wonderful for millennials...with the man buns...

For those interested: test eval on accurate shooter

http://bulletin.accurateshooter.com...-ts15-5-powder-outstanding-test-results/

Definitely looking to try it out whenever it eventually shows up on shelves

was thinking about the 22.250 with it, especially in the one with a one in 7 twist, with 75, 80, 88 grain bullets, and other in the 80 grain range from some of the other than Hornady...

I have nicknamed the 22-250 AI with a 1:7 twist the 22-250 VK...hope it takes

I have yet to see R15.5 in my area, Pittsburgh PA.

There is nothing on their website concerning this powder at all. WTF?

I meant on Alliant website.

I just picked up 2 lbs. of this powder TS15.5 should work for a heaver bullet in a 308 win.
Or, whatever you think it's good for?

Any up dates for this powder?

Thanks

https://www.alliantpowder.com/products/powder/reloderts15-5.aspx

https://www.alliantpowder.com/reloaders/Powder.aspx?powderid=43

I have loads for a couple of cartridges using RL-15 that I want to try RL-15.5 on.

I've been pinged twice on some, probably time to buy a couple pounds...

For a Whelen I loaded some 250 speers over this stuff to figure out pressure, and also some 310 woodleighs. Unfortunately won't be able to shoot it for a few days.

About 58 grains will fit into an unfired norma/nolser case, pretty high up the case neck, but with the powder settled with a high-end vibratory device (electric toothbrush), I couldn't feel any or hear much compression under a 250 Speer at 3.35 COAL.

Probably get a little more into a fired case. Less if you seat deeper. From memory, I think the same cases hold about 60 or 61gr of RL-15 at that COAL without crunching.

I have pretty good data from this same rifle using RL-15 for various 250's. I'll report back.

Last night, as I lay in bed, thinking about this powder; I thought about using it in my 338-06. Then I was to sleep. lol

As time permits, I'll prolly try some in my 338-06.

Happy Saturday!

https://bulletin.accurateshooter.co...outstanding-test-results/comment-page-1/

I’ll be watching.

They had a bunch at a local shop the other day but it was $55/pound so I passed. I spent my change on a blr81 in 358 win instead and as I was leaving thought that 15.5 would probably do well in the 358.

Bb

I've developed loads for the .338 WM with 200 grain E-Tips and .375 H&H with 270 grain TSX using RL 15.5. Charge weights are similar to what I have used before with RL 15. I'm getting some additional velocity and good accuracy with RL 15.5 plus it's more temperature stable. I like it!

Nice to see some good news is coming forward regarding 15.5 powder.

I'm waiting for 15 3/4 to come out..

lol.......I like it!

Sorry, no 15 3/4 coming. Next up is 15.70 for Winchesters only. Next will be 15.99 for the savage people.

I was thinking. 6 7/8's

I like that. I'm kind of savage.. I look forward to trying that model 70 powder out though.

That made me laugh..

I loaded a box of .308 Win with 180 gr ballistic tips and RL15.5 and I like it. FC brass, Fed 210 primers, 45.0 gr of RL15.5. Did not chrono. A couple rifles went .5 MOA for 3 shots. A couple other rifles were in the 1 MOA neighborhood. I also shot 180 gr coated accubonds and they shot well. Only issue is that 45.0 gr is pretty full in a FC case, up to case neck.

I'm about to load some up to try. Hornady has 338-06 RL-15 data for 200 (57.1 gr max), 225 (54.2 gr max), and 250 (50.9 gr max) grain bullets, so it should be possible to do some work with RL 15.5 using those numbers. They got 2900', 2700', and 2500' respectively (23.5" barrel) for the three weights with RL-15 so the chrono would help stay sane. Also looks like running out of case capacity won't be a factor. Could be an ideal sized case for this powder.

Interesting, Hornady also got 2900' with the 165-168 grain in the 30-06 with 54.2/RL-15, so that might be a good one too for RL-15.5

Rex

I'm a bit of a dope for not having figured out that Alliant actually has 30-06 data for RL-15.5 on their site. No need to extrapolate from RL-15 data:
Hope this Alliant Link works.
Will shoot this powder in both 338-06 and 9.3x62 tomorrow and report back.
Rex

I am back from the range with stuff to report on RL-15.5 in the 338-06 and the 9.3x62.
About the rifles - both are JES rebored 1903 Springfields. The 9.3 has about a 23.5" barrel and the 338 is 19" long. With previous loads, the 9.3 has been extremely accurate but the .338 has not yet shot well for me. Both rifles have Leupold M8 fixed 4X scopes, a tiny compact on the 9.3, and a full sized on the .338. Both rifles have long throats and the bullets are loaded to 3.375" for magazine length. Lapua brass for the 9.3, necked up FC 30-06 for the .338. All primers are CCI 200.
My velocity goals for the 9.3 match the good data Mule Deer has published for 60K PSI-ish pressures, and for the 338-06, I am looking for about 100 FPS less than the Hornady max data show due to the 4.5" shorter barrel.
That means ~2650 FPS for the 250AB and just under 2500 for the 286 PT (today I used the 250AB and a no-name 285RN for testing. I bought a few big bags from some guy that got them from an estate. They look just like PPU 285 or Lapua Mega 285).
For the 338-06 I'm looking for 2400' for the Hornady 250RN and 2600 for the 225 SP. I shot both those bullets today.
I loaded two rounds each for three charges each to get in the ballpark. Below I will try to summarize the results but the formatting might get goofy when I post it. I list the two speeds and the center-to-center distance between the two rounds.

9.3x62, 250 NAB (goal = 2650')
60 grains - 2421, 2454, 0.27"
61 grains - 2511, 2494, 0.45"
62 grains - 2542, 2547, 0.20"
Summary - looks like outstanding accuracy potential, and room for 1.5 to 2.0 grains more powder to reach the goal.

9.3x62, No-Name 285RN (goal = 2500')
58 grains - 2290, 2266, 0.46"
59 grains - 2312, 2314, N/A, the first round hit just off my paper - it was just about 2"
60 grains - 2368, 2358, 0.95"
Summary - looks like at least 2 more grains needed to reach the speed goal.

338-06, 250 Hor RN (goal = 2400')
50 grains - 2233, 2230, 1.00"
51 grains - 2292, 2266, 2.23"
52 grains - 2330, 2322, 1.70"
Summary - maybe another 1.5 grains to reach 2400', accuracy potential not exciting (but it is certainly minute-of-moose, and about as good as this rifle has ever shot before)

338-06, 225 Hor SP Interlock (goal = 2600')
54 grains - 2504, 2489, 0.47"
55 grains - 2549, 2530, 1.06"
56 grains - 2594, 2589, No kidding one hole. Barely perceptible elongation - can't measure it.
Summary - Excellent! I hit my speed goal of ~2600' and the accuracy potential looks good. Very excited to repeat the 56 grain charge with more rounds. These 6 rounds formed a cluster much smaller than the average 3-shot group this rifle has delivered with previous loads.

I hope these results will help others develop their own loads with RL-15.5. Please post your results. Don't forget my rifles have long throats and are loaded to magazine length. I will sneak up closer to the velocity goals next Wednesday and report back. Will also try the 210 NPT in the 338-06 and see if it plays well with RL15.5. I really hope so but can be happy forever with the 225 Hor SP if it keeps up what it did today.

Cheers,
Rex

Is the bulkiness of the powder giving any problems in either case? I can get exactly 59 grains (settled) into a fired Nosler/norma 35 Whelen case with 250 partitions at 3.33 COAL. 59.5gr needs a deeper setting on the seating die to get the same COAL.

Should get chrono data tomorrow. 58gr of this stuff under a 250 Speer is a very mild feeling load... gives 2450 fps from a 20" Whelen with a very short throat, primers completely round. Hoping to break 2500 but not sure the powder will fit. Obviously 2450 is fine. I think I'd be at 2400 fps in a SAAMI chamber but I'll test that tomorrow, too.

It is looking like the 338-06 and 9.3x62 cases are going to be OK with RL-15.5, bulk-wise with the bullets listed above. I only have a 4" drop tube but it may be helping. I ran out of room in the .308 with 155 Scenars.
I'll be loading my follow-on test rounds later today and can report back with a bulk assessment. My Whelen is an AI with just slightly more capacity than the standard, so I hope I can get the 2650' I was running with 250 PT and 65/2000-MR. That was a great load but the same performance with temp-resistance would be a plus.
Cheers,
Rex

In the 9.3x62 in once fired Lapua cases, I loaded up to 62 grains RL-15.5 under the Lapua 285gr Mega, and 64 grains under the Nosler 250 AB, both bullets at 3.375" COAL. Here is what the case fill looked like with my little 4" RCBS drop tube.


The 285 Mega seated perfectly, since it's a short bullet, and the base just snugged right up to the 62 grain charge

The 250 AB required some decent compression but seated fine. Both it and the 286 PT extend below the case shoulder at 3.375"

I cobbled up an 18" aluminum drop tube and dropped the same 64 grain charge as pictured above with the 250 AB, and it definitely helped. It makes the 64 grain charge look closer to the original 62 grain charge pictured above with the 285 Mega.

So bulk is an issue, but I think I'm going to be fine in my rifle, with the 3.4" magazine and long throat. That long throat is standard for most all 9.3x62s so RL-15.5 may be a player for this cartridge.
I will follow up with the loading bulk for the .338-06.
From prior testing, I know that my 35 Whelen AI cases have about 0.3 grains of water more capacity than my 9.3x62, when both are filled to the base of a 250 grain bullet seated 3.375", so I am hopeful for that chambering as well.

Cheers,
Rex

Rex, Do you have any comparison of RL15.5 bulking compared with H4350? I've grown aggravated with the large lot to lot variation & poor availability of H4350 & have found substitutes for it in most cartridges. Still searching for a sub. in 22-250 Imp with 53s & 338-06 Imp with 200/210s. Good lots of the Hodgdon powder give stellar accuracy & good velocity with fairly full cases (about like your 2nd pic or a bit fuller) after a very slow pour & tapping. Normally moving to the next quicker powder would be the next thing to try, but other than Big Game showing promise in the 338, nothing else has worked out. I have hopes for 15.5, but wont bother jumping on any if it's notably bulkier than H4350. Thanks for any information.

358WCF,
My two 338-06s are both the standard version, so slightly less volume than your AI. That said, my first look at loading 15.5 in my 338-06 carbine indicates case capacity is not going to be a big issue.
Since it's a faster powder than H4350 (or at least I am assuming it is - am I mistaken?) we would be using lighter charges of RL-15.5 than H4350.
I have plenty of H4350 and can do a comparison for you. I can compare the visual bulk of two identical charges, or set my measure to a fixed volume and compare the weights of two identical volumes. How would you like me to proceed?

Regardless, I will probably load up my next round of 338-06 with RL-15.5 later tonight and can provide pictures similar to those above. My sense is bulkiness will be less of an issue in the 338-06 than the "Nine-Three."

Cheers,
Rex

358WCF, et. al.
I just loaded a few 338-06 with RL-15.5
Another 6 of the 225 Hor. SP over 56/RL-15.5, at 3.375" OAL (.055 off the lands). This previously met my velocity goal of ~2600' in the Springfield's 19" carbine barrel.
Loaded 3 of the 210 NPT over 56/RL-15.5, and 3 over 57/RL-15.5, all at 3.305" OAL (.025 off the lands).

In all of these the case fill looked just about 100% - right to the base of the seated bullet with no compression needed.

Will report on the accuracy and velocity of the 210 NPT load when I get to fire them.

Anxious to try this powder in my 24" Mauser 338-06.

Cheers,
Rex

In an AI I think you might get close to your 2000-MR speeds. They act very similar in a standard Whelen case under 310 woodleighs. Big Game and 2000-MR seem very slightly slower than RL 15.5 in that application...RL 15.5 started showing pressure maybe 20-30 fps earlier. Very close, at any rate.

I am thinking Big Game might nose out RL15.5 in the standard Whelen case but I should know more tomorrow.

Rex,

I realize that 15.5 is a bit quicker than H4350. In the 338-06 Imp. I've managed to get 66gr of H4350 seated under a bullet in fully formed 90s era WW '06 brass. Fully formed, it holds 72.6gr of H20 filled to the top after sizing. At 66gr. it's bit crunchy when seating the bullet, but shoots well at excellent speed. No pressure sign at all & case life is long, so... It's way better than initial expectations, but I'm still wondering if a quicker powder will do anything better? Plus there's the H4350 lot to lot & availability problems. The slower lots of H4350 dropped 250fps in the 22-250Imp. & groups turned to schidt. The bigger bore 338 isn't quite as drastic, but it still changes a bit. Leaving no turd unstoned so to speak, I'm curious if 15.5 will solve the ballistic problem. Availability is a whole 'nuther thing. According to my notes RL16 also ran out of case space at 65-66gr at about 100fps less than the 4350 load with mediocre accuracy, so again, a slightly quicker powder may be a winner. If you could set your powder measure for your chosen 15.5 weight, & after you're done loading dump some H4350 at that setting & get a weight that would likely tell all that's needed. A picture of the 2 powders position in the cases at the same weight could also be worth 1000 words if you have the opportunity without too much trouble.

Thanks so much for your trouble-358

OK Mr. 358WCF, here is a little comparison for you.
First pic is 57 grains of RL-15.5 just dumped into a 338-06 case (fairly heavy 202 grain FC 30-06 necked up). No long drop tube or trickling the powder.

Second pic is the same volume of H4350 in the same case, same techniques, no changes to the powder measure. Naturally it looks about the same. But, when I weighed this equal volume charge, it was 60 grains, over a 5% increase in weight per volume.

So then I removed powder from the scale until the H4350 charge weighed 57 grains and dumped it back into the same case.

My guess is you will not have a volume problem with sane loads in your 338-06 AI with RL 15.5.

Regards,
Rex

Thanks for the good information Rex. Hopefully it's enough quicker that the extra bulk wont be a concern. Looks like it should be worth getting a # or 3 next time it comes around.

Here is a follow-up to the data quoted above, with the increased charges based on the prior results. I did not shoot more of the .338 250 RN, but tried out the 210 PT. Three shot groups today. I'll give the average speed and the SD, (even though 3-shot groups don't provide statistical significance to SD) and group size.
I am suspicious about the second group with each bullet in the .338-06, that I may have experienced a scope issue, so the suddenly huge groups with the second charge under each bullet may be caused by a scope problem.

9.3x62, 250 NAB (goal = 2650')
63 grains - 2579', SD = 9, 1.29"
64 grains - 2604', SD = 8, 1.15"
Summary - Decent accuracy. At least a grain of powder shy of the velocity goal. Probably can't squeeze any more in.

9.3x62, Lapua 285 Mega (goal = 2500')
61 grains - 2411', SD = 14, 1.63"
62 grains - 2447', SD = 9, 0.87"
Summary - like the 250 AB, about 50 FPS shy of the speed goal, but a perfectly acceptable load. Next trip out I will load a few of my precious 286 Partitions over the 62 grain charge and see how they do. They have a little more bearing surface and may give a touch more pressure/velocity. Everything in the 9.3 today appeared very mild, pressure-wise.

338-06, 210 PT (no particular speed goal. Recall this is a 19" barrel)
56 grains - 2611', SD = 14, 1.75"
57 grains - 2655, SD = 29 (maybe one bad, very low, chrono reading), 3.10"

338-06, 225 Hor SP Interlock (goal = 2600')
56 grains (6 rounds, two 3-shot groups, scope adjusted prior to the second)- 2585', SD = 9, 1.63", 2.95"

Summary - Close enough on the speed goal. Going to swap scopes and see if the big groups from the second charge with both bullets was due to a scope problem incurred when making an adjustment prior to firing the second charge with each bullet.

Hope this information helps out some of you. I shot one group with the 30-06 that is promising and will make a separate post for that.
Rex

Yesterday I also shot one group with RL-15.5 in the 30-06 that was promising.
155 Scenar, .020" off lands at 3.330" OAL
54/RL-15.5
CC1 200
Fed case.

2975 FPS with an SD of 7. I pulled the second shot and still the group was 0.85".

The 30-06 may end up being a case in which RL-15.5 really shines. Plenty of data for it on Alliant's site too. This is my buddy's rifle and I am doing accurizing and load work with Noslers for his sheep hunt. I just threw that one load above in since I was taking it to the range anyway. Will try this out in my own 30-06 rifles when I get the chance.

Cheers,
Rex

I just found this, and it's exactly what I was looking for. Thanks for the detail.

Well, I have a bunch more loads in the 35 Whelen AI and the 9.3x62 I am taking to the range in two days and will report back. Glad the information was useful to you. There is so little "gouge" out there on this powder I figured it was worth putting some detail into the report.

Will write back Thursday,
Rex

I took 9.3x62 loads with the 250 AB and the 286 Part to the range this week.
I ran 64 and 65 grains under the 250 AB at 3.38 OAL (still a big jump to the lands) and 62 and 63 under the 286 PT at the same OAL. Lapua cases, CCI200. #-shot groups:
250 AB, 64/RL-15.5 = 2622 FPS, 17 SD, 1.15"
250 AB, 65/RL-15.5 = 2633 FPS, 3 SD, 2.15" (horizontal strung, centered on POI) Note the slight speed increase for a full grain more powder.
286 PT, 62/RL-15.5 = 2420 FPS, 13 SD, 1.95"
286 PT, 63/RL-15.5 = 2456 FPS, ES of 11 (only got two chrono readings), 2.45"

I will go with the 64 grain load under the 250 AB for my upcoming elk hunt, but think I will stick with Mule Deer's published load of 66/Big Game for the 286 PT. It is a good shooter in my rifle.

I noted that with the 250 AB sighted 3" high at 100 yards, the 286 PT hits right about point of aim at that distance with no scope changes. This is vaguely familiar to some other account of a similar cartridge, but I don't recall it clearly enough to expound.

Cheers,
Rex

9.3X62 Bad to the bone.

Opening morning on my elk hunt tomorrow. Using the 64/RL-15.5 under the 250 AB in the Nine-Three as my prime. 63/RL-15.5 under the 225 AB in the 35 Whelen AI as the back-up/rainy day rifle.
Wish me luck.
Rex

Thanks to whomever wished me luck 'cause it worked!

Cheers,
Rex

Nice work! Congrats!

RL15.5 under a 250 partition got me a moose with the Whelen a few weeks back. I still want to check temp stability when it's colder.

Congrats on the elk!

Thanks. Please share the details of your load.
Rex

I think I already posted this somewhere but:
35 Whelen std
59.5 RL15.5
250 Partition.
once fired Nosler/Norma brass (that much powder won't fit in virgin brass)
CCI mag primer
3.34 COAL (might be 3.35 but can't remember off top of my head).
2500 fps from a 20" barrel (shorter throat than SAAMI), ES of about 18 over 20 shots.
3/4 MOA.
Not quite as accurate and slightly slower than my RL-15 and MR-2000 loads, but good enough for what it's intended for.
You either have to settle the powder with a vibratory device or trickle it very slowly or expect a lot of powder crunch.

Thanks gents, for your work with RL-15.5 It's going to be a while before I get out and do some testing.

I have to heal-up from my surgery on my back.

Take care.