Best powders for 300 WSM?

[NamibHunter]

Some context: Have a switch barrel short action MPA BA rifle in 6.5 CM, with the West Texas Ordnance SwitchLug system. I want to make full use of the barrel switching / caliber switching capabilities of the rifle system, and get a new barrel in the largest possibly 300 cal magnum cartridge that will fit in the Axiom short action. Single feeding is fine. Idea is to shoot 210 to 240 grain bullets. Yes I realize that a 300 WSM is a compromise compared to say building a new 300 Norma or a 300 RUM, and that the short action choice will cost me 200-300 fps in speed. But there are budget limitations, so want to buy only a new barrel and a new magnum bolt, and use the same MPA chassis, Curtis Axiom action, Triggertech Special trigger and the existing ATACR scope. I am trying to get an idea of what speed and therefore wind drift numbers i can expect at 1,500 yards, and how far i could stretch the distance before a heavy high BC bullet will go subsonic. My “ELR on a tight budget” project.

The latest Hornady load book predicts a rather slow 2650 fps from a 24” barrel for the 220 gn ELDM, for a multitude of powders, and none really stand out. RL26, Win 760 and N570 are not in the list.

For comparison, a 300 RSAUM, which has less case capacity, using Win 760 and driving a 220 gn bullet gets to 2700 fps from a 24” barrel, according to the Hornady load data (11’th edition). So i think their load data is rather incomplete - and perhaps a little conservative. What double base powders will do better than 2650 fps for a 220 gn?

Assuming 25 fps per inch of additional barrel length, maybe i can hope to see 2750 to 2800fps from a 28” barrel?

Below is load data for the 300 WSM, 24” barrel, 220 gn bullet:

 

[DocRDS]

The big bullet powders I read about everyone raving on is H1000, Retumbo, RL-26, IMR7977 and IMR 8133. YMMV.

Warning my research was done for 300 WM not WSM, but I bet the prefered powders won't change much.

 

[NamibHunter]

The big bullet powders I read about everyone raving on is H1000, Retumbo, RL-26, IMR7977 and IMR 8133. YMMV.

Warning my research was done for 300 WM not WSM, but I bet the prefered powders won't change much.

Thanks for the advice. Will do some more research on the hunting forums.

It seems to me that for bullets in the 150 to 190 grain weight range, there is maybe a 50-75 fps difference between the 300 WSM and the much larger 300 Winmag, but for the 210-250 grain range the speed difference goes up to 150 to 200 fps. Is that correct?

 

[lightman]

Mine likes H4831SC.

 

[Freediver111]

I’m using 4831sc in a 22” benchmark barreled 300 wsm with 212 gr eld-x. Norma brass, seated .09” off the lands (seating depth test found this to be the best jump, which surprised me a little). Velocity is 2780 FPS. Not pushing too hard, but it is a very lightly compressed load due to seating the bullet a little deeper. Charge is 65.5 grains, and my rifle is a SAMMI spec’d chamber.

 

[Steel head]

Mine likes H4831SC.

That’s where I’d look first.

 

[DocRDS]

Thanks for the advice. Will do some more research on the hunting forums.

It seems to me that for bullets in the 150 to 190 grain weight range, there is maybe a 50-75 fps difference between the 300 WSM and the much larger 300 Winmag, but for the 210-250 grain range the speed difference goes up to 150 to 200 fps. Is that correct?

I really don't know--My only exposure to WSM is because the reloading threads are combined.

And the 4831 is popular (and available) for the 300 Mags, but again, everyone gravitates towards those 'big bullet powders'

I did alse find in my tests yesterday that Hornady published loads were pretty conservative (at least for my firearm). There may be more room at the top, but as always: work up and observe carefully. For instance my 200 Hornady max pub load (76) was less that the 220 gr SMK pub load (78). I was a full 2 grains above max--no pressure. (2980 fps-- caveat--Hotter than crap on the range-100+ -- so EVERYTHING was fast yesterday and I worked up slowly).

 

[NamibHunter]

I heard that the guys at Patriot Valley got over 2800 fps out of a 300 WSM using N570, driving the super long 241 gn Seneca mono bullet, i think from a 26” barrel. [Btw the 241 Seneca is the highest BC (30 cal) bullet listed in Strelok today: G7 > 0.5]

Surprised that such a slow powder worked so well in the short mag case, presumably the 241 gn bullet is heavy enough to act more like a 250 gn 338 bullet in terms of barrel dwell time. And a longer barrel will probably accentuate that even more.

N560 might also be an option i guess?

 

[chase723]

RL23

 

[wpeach1912]

I have heard of superformance doing really well in 300 wsm. In my research, it seems that the slightly faster than H1000 powders tend to be the ticket. Which gets you H4831sc, superformance, maybe 7828, RL23, and Hybrid 100v

 

[NamibHunter]

Mine likes H4831SC.

What speed are you getting, bullet weight and barrel length?

 

[lightman]

What speed are you getting, bullet weight and barrel length?

I'm sorry that I didn't respond to this sooner. My Wife has been in the hospital.

70 grains behind a 168 Berger VLD Hunting bullet in Winchester brass runs in the 3010 FPS speed range. Thats max and over max in some books but I worked up to it carefully. No pressure signs and cases last forever.

 

[NamibHunter]

I'm sorry that I didn't respond to this sooner. My Wife has been in the hospital.

70 grains behind a 168 Berger VLD Hunting bullet in Winchester brass runs in the 3010 FPS speed range. Thats max and over max in some books but I worked up to it carefully. No pressure signs and cases last forever.

No problem! Family comes first. Hope she gets better soon.

Had a look at the commercial ammo listed in Strelok Pro. The 165/168 gn ammo runs about 3130 fps. The HSM 168 Berger HUNTING VLD runs 3109 fps, almost exactly your number.

Also had a look at the Hornady load manual (11’th edition) and for 165/168 projectiles, it list most powders at 3100 fps max, so very similar. Only W760 at 3150 and Superformance at 3200 fps exceed that, for a 24” barrel.

Presume you are running a 24” barrel?

 

[Devildog]

I’m having great luck with imr 4451 with 185 gr Berger vld’s

 

[NamibHunter]

I’m having great luck with imr 4451 with 185 gr Berger vld’s

Good to know. What speed did you get (and what is your barrel length)?

 

[Devildog]

Good to know. What speed did you get (and what is your barrel length)?

22” barrel running 2770 fps

 

[erikc641]

I'm running a 190 ABLR with 60.5 grains of RL16 @ 2836 ft/s (23" barrel, A-Bolt II)

 

[4thandbleek]

H4350, RL16, H4831sc, Probably in that order.

 

[NamibHunter]

Has anybody had any luck with 220-240 gn bullets in a 300 WSM? What speed and what powder (and barrel length)? RL26 seems like a good candidate. N570 was also mentioned.

Trying to find a way to shoot the new 0.308” very high BC projectiles out of a short action. Single feed is ok.

[I realize this caliber (and the twist rates of typical factory rifles) are not ideal for such heavy projectiles, but trying to avoid building a new 300 Norma rifle (cost!).]

 

[Freediver111]

Has anybody had any luck with 220-240 gn bullets in a 300 WSM? What speed and what powder (and barrel length)? RL26 seems like a good candidate. N570 was also mentioned.

Trying to find a way to way to shoot the new 0.308” very high BC projectiles out of a short action. Single feed is ok.

[I realize this caliber (and the twist rate of typical factory rifles) are not ideal for such heavy projectiles, but trying to avoid building a new 300 Norma rifle (cost!).]

Hate to say it, but I would stick to 200-215 projectiles in the 300 WSM. I just feel like velocity starts to nose dive beyond those weights and you won’t really gain much benefit going that heavy. BC and KE is negated when velocity drops that much. You want to shoot 220-240 gr bullets, move to a dedicated cartridge that has the powder capacity to push them 2800-2900. I forgot to mention my barrel is 1-9.5 twist. Wanted 1-9, but that wasn’t in stock for 4 months so settled on 1-9.5. I purposely wanted to shoot 200-215 gr bullets in mine. I also have no love for RL26. Great speed, but I had so many temp swings that I gave up on it.

 

[NamibHunter]

Hate to say it, but I would stick to 200-215 projectiles in the 300 WSM. I just feel like velocity starts to nose dive beyond those weights and you won’t really gain much benefit going that heavy. BC and KE is negated when velocity drops that much. You want to shoot 220-240 gr bullets, move to a dedicated cartridge that has the powder capacity to push them 2800-2900. I forgot to mention my barrel is 1-9.5 twist. Wanted 1-9, but that wasn’t in stock for 4 months so settled on 1-9.5. I purposely wanted to shoot 200-215 gr bullets in mine. I also have no love for RL26. Great speed, but I had so many temp swings that I gave up on it.

Well, you may have a point!

If i can get the 212 Seneca with a claimed G7 BC of 0.46 to 2,900 fps or a little more, the bullet stays supersonic to 2,200 yards, and the 1 mile wind drift for a full value 10 mph wind is only 6.25 MOA. Not bad at all.

Supersonic beyond 2,000 yards is nothing to sneeze at, from a short action rifle.

 

[NamibHunter]

In contrast, the 241 Seneca with a claimed G7 BC of 0.555 (and no that is not a typo) launched at 2,700 fps (from a 28” barrel) has about 0.9 MOA less wind drift at a mile (5.4 vs 6.3 MOA). It is supersonic for an additional 200 yards (2,400 vs 2,200 yards).

There is a difference at ELR distances, but not massive.

 

[Schw15]

In contrast, the 241 Seneca fired at 2,700 fps (from a 28” barrel) has 0.9 MOA less wind drift at a mile (5.4 vs 6.3 MOA), and it is supersonic for an additional 200 yards.

There is a difference, but not massive.

I asked the same question in the long range part. 300 wsm with 212 or 241. Loaded long ect. We have the same idea but I didn't get much. Mr. Sherman is coming out with a new case 300 mega. It's like a 300 wsm but holds more powder. His max is like 78 the new case 85+. Might be a great option

 

[LongRangeActual]

For what it's worth, I have a 300wsm with a 27" benchmark MTU. 1:9. I shoot 230g Atips with H1000 @2845. Been out to the 2 mile target regularly. I'm obviously compressed.

 

[4thandbleek]

It was imr-4350,now RL-17.I don't have my notes handy now,but it works real well with 125-190gr bullets.

 

[canezach]

RL23

Saw the thread title and came to post this. Second on RL23

 

[Fair chase]

RL17 here

 

[NamibHunter]

T

I really don't know--My only exposure to WSM is because the reloading threads are combined.

And the 4831 is popular (and available) for the 300 Mags, but again, everyone gravitates towards those 'big bullet powders'

I did alse find in my tests yesterday that Hornady published loads were pretty conservative (at least for my firearm). There may be more room at the top, but as always: work up and observe carefully. For instance my 200 Hornady max pub load (76) was less that the 220 gr SMK pub load (78). I was a full 2 grains above max--no pressure. (2980 fps-- caveat--Hotter than crap on the range-100+ -- so EVERYTHING was fast yesterday and I worked up slowly).

Thanks much, this is good info!

As luck would have it, I have some H4831SC already, will try it first.

 

[NamibHunter]

Th

It was imr-4350,now RL-17.I don't have my notes handy now,but it works real well with 125-190gr bullets.

That 1840

For what it's worth, I have a 300wsm with a 27" benchmark MTU. 1:9. I shoot 230g Atips with H1000 @2845. Been out to the 2 mile target regularly. I'm obviously compressed.

That 2845 fps for a 230 gn is pretty impressive, i assume a 28” will probably get you to 2900 fps or very close.

Would it be reasonable to assume a speed loss about 100 fps if you add 10 gn to the bullet weight, so a 241 Seneca should/could/maybe do 2790 fps, or do you lose more than 100 fps?

 

[BoltActionBrotherhood]

I'm running the 180gr, out of a 16 inch barrel getting right under 3000 fps using RL26 in my 300 wsm.
If I run it up to 3k I start seeing pressure issues.

 

[Steel head]

I'm running the 180gr, out of a 16 inch barrel getting right under 3000 fps using RL26 in my 300 wsm.
If I run it up to 3k I start seeing pressure issues.

16” barrel?

 

[Choid]

There isn't a cartridge in that class where RL26 shouldn't be the first option. 17 and 23 are also good. Then the rest.

 

[BoltActionBrotherhood]

16” barrel?

Yes sir!

 

[TEUFEL820]

I use RL-26 exclusively for the 300 WSM. Berger 208 LRHT at 3030 fps from a 26" tube 1:10

 

[Cbass1019]

I use RL-26 exclusively for the 300 WSM. Berger 208 LRHT at 3030 fps from a 26" tube 1:10

What's your oal?

 

[NamibHunter]

Need some advice:

I see Vihtavouri powders in stock more frequently now, and they claim “extreme temperature stability” and being “insensitive to humidity changes”. Which is a good thing.

Does anybody have test results regarding temp sensitivity in any of the 300 magnum calibers for these powders: N560, N565, N568 or N570 in the 300 WSM?

Any max speed, SD, or group size results with heavy bullets in the 200 to 230 gn weight range for these powders. Please be so kind as to provide barrel length as well, just to make it easier to interpret your test data.

The Viht reloading page for 300 WSM (on their official web site) only goes out to 200 gn projectiles and only mentions N560. They do list the other slower powders for 300 Winmag and 300 PRC, which makes me think they could work well in a 30” barrel shooting the heavies…

BTW: I’m testing 220 Berger and the 230 Atip next. Had good results already with Hornady 225 ELDM with H4831 so far.

 

[Pootyng]

Need some advice:

I see Vihtavouri powders in stock more frequently now, and they claim “extreme temperature stability” and being “insensitive to humidity changes”. Which is a good thing.

Does anybody have test results regarding temp sensitivity in any of the 300 magnum calibers for these powders: N560, N565, N568 or N570 in the 300 WSM?

Any max speed, SD, or group size results with heavy bullets in the 200 to 230 gn weight range for these powders. Please be so kind as to provide barrel length as well, just to make it easier to your test interpret data.

The Viht reloading page for 300 WSM (on their official web site) only goes out to 200 gn projectiles and only mentions N560. They do list the other slower powders for 300 Winmag and 300 PRC, which makes me think they could work well in a 30” barrel shooting the heavies…

BTW: I’m testing 220 Berger and the 230 Atip next. Had good results already with Hornady 225 ELDM with H4831 so far.

I emailed vihtavuori to ask about data for 200-212 grain bullets and they sent me their data. I hope this helps.
I initially asked for N568 data for those weights but they said there wasn’t enough case capacity to reach optimal velocity.

 

[NamibHunter]

For what it's worth, I have a 300wsm with a 27" benchmark MTU. 1:9. I shoot 230g Atips with H1000 @2845. Been out to the 2 mile target regularly. I'm obviously compressed.

That is a pretty good speed for such a heavy bullet. I guess you have a fast barrel? How many reloads are you getting, and what brass are you using?

Tried the 230 Atips recently and got to 2820 fps before heavy bolt lift (and clickers) kicked in, 30” barrel, using RL-23 in 17x fired ADG brass. Brass is getting old and my Hornady die does not size the base of the case enough. Primer pockets are also starting to feel loose.

Found a nice wide node lower down at 2765 fps, and that worked quite well. Slightly compressed load, in a chamber with very long freebore and loaded to a small jump, single feed only. I’m happy with that speed and the batch of ammo was clicker free. Best seating depth (6 thou jump) gave three bullet holes touching in a 0.5” group.

Thanks for the tip to try RL-23. That was helpful.

Also RL23 seems to be fairly insensitive to ambient temp changes.

 

[LongRangeActual]

Tried the 230 Atips recently and got to 2820 fps before heavy bolt lift kicked in, using RL-23. ADG brass. Found a nice wide node lower down at 2765 fps, and that worked quite well. Slightly compressed load, in a chamber with very long freebore and loaded to a small jump. I’m happy with that speed. Best seating dept gave three bullet holes touching in a 0.5” group.

Thanks for the tip to try RL-23! That was helpful.

Also RL23 seems to be fairly insensitive to ambient temp changes.

23 works well but i stay away from if if at all possible. Im glad it worked out for you. What other powder do you have at your disposal?

 

[NamibHunter]

23 works well but i stay away from if if at all possible. Im glad it worked out for you. What other powder do you have at your disposal?

Curious, what is the reason for avoiding RL-23? I realize it is a double base powder and will probably/likely erode the lands much faster than a single base powder.

I have H1000, RL-17, N165, N170, N560, N565, H4831SC, 7828SSC, H4350, IMR4350 and Retumbo.

Lead core bullets on hand:

Berger 200.20x Hybrid
Berger 208 LRHT
Berger 220 LRHT (700)
Hornady 225 ELDM (400)
Hornady 230 Atip (100)

Monolithic copper projectiles:
Barnes 180 TTSX
Warner 198 Flatline (100)

 

[LongRangeActual]

I don’t mean so much to stay away from it “all together”. I just mean due to its sensitivity if I can use something else I will.

If you want to play with the 230s, use them with h1000. You’re single Feeding the big bullets?

 

[NamibHunter]

I have tried H1000 with HBN coated 225 ELDM and coated 230 Atips. It produced adequate velocity, but the 300 WSM case capacity (about 81) is a little on the small side, and i probably should not have gone for coated bullets (they typically need about 1.5 gn more powder to get back to the same speed). Might try it again without the HBN.

Not doubting your experience. I did a search to see if RL-23 is temp sensitive, and most people seem to think it is quite stable. Have not tested that, so not really sure. Curious what others have found.

You are being redirected...

[I do realize that caliber/chambering has an effect too, and proving that a powder is stable in one does not prove it will perform the same in another chambering. Also primer compound is not actually temp stable and that has some effect on muzzle velocity.]