Quickload question for 300WSM


Active Member
Apr 8, 2012
Can someone help me out. I have been reloading for a couple years and I make no claims to be any where near an expert.

I reloaded for my 300WSM, a Winchester M70 (Wal-Mart special), 24" barrel, Hornady 180grain SST, Federal Brass, 66 grains of RE-17, CCI200 primer, COAL of 2.262 which should be about .003" of the lands.

The end result was a .303" group at 3086fps average. Is this a safe load? I am more about accuracy than speed.

Yes I did start at a lower charge and worked up. I dont think I see any obvious signs of over-pressure.

I am interested in what people "who know", or have the ability to tell me if this load is safe to use.

Thanks for all the help.
Based on QL, it is a hot load @ 71Kpsi.
While new brass may take it, I can't imagine it will for more than a couple reloads & you'll have your pressure signs, and degrading results.

It's a low fill ratio @ only ~93% with a powder that's too fast for capacity IMO.
66 grains is Alliant's max load recommendation on thier website. So far I agree with them. 66 is as far as I felt comfortable pushing it for load testing.

I shoot 180 Accubonds over 65.0 gr of RL-17 in my Model-70 custom, Long Action 300WSM. I use Nosler brass, & it's on its 3 loading so far. Bullets seated .015 off lands with a c.o.a.l. of 3.004 your clear back at 2.262 so your capacity ratio is better than mine for a hot powder, but I had er throated long for flingin 200gr Accubonds too.

Tested all the way from 63gr to 66gr in .5 gr increments, 95* temps with no real issues, but it just seemed "too hot" of a load at 66gr. Slightly stiff bolt but barely noticeable. No flattened or cratered primers, no shiny marks on brass etc. just felt a bit too hot. So I backed off to 65 gr in .2 gr increments where I found the best accuracy.
I hunt Hells Canyon in August for bear, in temps up in the hundred & teens, so I'd rather err on the safe side..... If you consider 1 gr under max the safe side:Dgun)
IMO 66gr really is about where max safe load was in a moderate climate. I didn't feel comfy at 66gr personally for my hunting climate. I'm good with 65 tho.

As a side note, I'm shooting over max with 140 Accubonds over RL-19 in my 270WSM in Hells Canyon with zero issues what so ever.

I really like Alliant RL powders.
If you can detect no signs of excessive pressure and you can get 4-5 reloads without stressing the brass,I think that this is a safe load for your gun.

The Alliant web site gives 66 grains as the Max load with a 180 grain bullet, as Winmag just stated. They used Fed cases, Fed 215 primers for a velocity of 3082 ft/sec., so you results comes close to matching their data.

I have loaded 68 grains of RL-17, WW cases, Fed 215 primers, and 168 grain Berger in my Model 70 Winchester. This load produced 3132 ft/sec velocity and I not feel that this was too hot for my gun.

I have also fired Federal factory ammo loaded with 180 grains Nosler solid base bullets in my gun. This load was not very accurate in but it did produce 3055 ft/sec velocity. So it is very possible to get over 3000 ft/sec with a 180 grain bullet without exceeding pressure limits.
He's well exceeding SAAMI pressure limits, or his velocity would not be so.
But as mentioned, that don't mean it's a problem.
Thanks for all the help guys. I also e-mailed Alliant and they stated it should be OK. With that being said, since I am already on my hunting trip, I will work backwards in .2 grains as suggested by WinMag when I get back home.

The thing that kind of sucks since I am more into accuracy is that I am getting great accuracy!!

On a good note my wife shot her 1st 4X5 this morning. It wasn't very big but she is happy. 7MM-08 120grain Nosler BT, 3035fps. She got it 140yds away free standing.

Once again thanks for all the help and quick responses.
I've been shooting 66 grains of RL17 behind 180 grain SST's for about a year. 1/2 MOA at 200 yds. with a Savage model 16 stainless L.H. 300WSM. Switching from 165's to 180's and from RL19 to RL17 made a big difference. I think I'm .20 off the lands.


So how much would I need to back off to get back to SAMMI specs? At 65grains I was getting .9something groups.

I guess I am asking if I back it off to much and my groups start opening significantly would this recipe be worth it?

If I can back off to say 65.6 grains and still get about .5" accuracy would I be safe, pressure wise?


Thank you for your input!
Warning! This thread is more than 12 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Recent Posts