New to the 300 Win Mag

[Ksmirk]

Morning fella's, sorry for the bother but I really didn't find in the search what I was after.... I did find some useful info so my question won't be as crazy

I just started out with the 300wm and while I'm not new to loading there's just a mess of powder blowing up by my face so I'd like to be sure I'm going the right direction.

I know H1000 and the 215 Berger is the peas in a pod loading but I have close to 7# retumbo I'd like to get rid of and a little info on the chamber as I have throated the chamber to where I am at the lands with a reading of 2.945" so I can seat longer. This past weekend I loaded up to 81.5gr powder and never hit anything that resembled pressure sign and the velocity was 3065 question is should I push until I see pressure and back off or call it quits? Later,

Kirk

 

[3stooge]

That seems really fast. I can see why you're asking. I don't have an answer, but I'm curious to see what someone with experience has to say. If I remember when I get home tonight, I'll run a quickload scenario and try to get an idea of what it predicts.

Did you find acceptable accuracy?

 

[Ksmirk]

The fellas I sorta copied their reamer specs are shooting at 3050fps so I'm real close. With these being loaded long the book states a normal loaded 300 would be compressed at 81.0gr mine 81.5gr you could still hear the powder shaking around. I've been loading 243, 308 class rounds for many years and sorta know what I can and can't get away with but the 300 sure will hold a mess more powder!

I can find all sorts of info on H1000 and the 215 Berger but like I said before I go down that road I'd like to use up the Retumbo.

As for accuracy all the loads tested were fair at least for a 12-17mph wind, I did try a few out at 100 yards and didn't have a problem keeping them right at an inch but it's a new barrel and well the wind was ridiculous but at least I got good numbers for some loads. Later,

Kirk

 

[Ksmirk]

Oh the 2.945" is the Ogive length COAL is right at 3.742ish give or take for bullet points.... thought I wrote that in the first post but guess I left it out. Later,

Kirk

 

[Dosh]

Kirk, do your loads fit your mag?

 

[Ksmirk]

No I built this rifle as a single shot, I've got a couple rifles I hunt with this one is just for steel out there a way. My brother is building one as well and he will be loading mag length but using a 338 lapua CID length but he is still a month or so out on his stock showing up. Later,

Kirk

 

[Ksmirk]

I figured for sure I'd get some input here, I guess no one is loading Retumbo and long loads. Guess just load the thing like I would a 308 or 243 and figure out where I find pressure signs and where the velocity ends up as long as it shoots well run with it. Later,

Kirk

 

[BEEMAN]

I figured for sure I'd get some input here, I guess no one is loading Retumbo and long loads. Guess just load the thing like I would a 308 or 243 and figure out where I find pressure signs and where the velocity ends up as long as it shoots well run with it. Later,

Kirk

I would stop there if it is shooting good. The velocity is great. How long of a barrel do you have? I use H1000 at 79 gr out of a 26" Brux and hit 3000 fps with the 215. Velocity and groups are awesome so I stopped at 79 gr.

 

[dfanonymous]

I figured for sure I'd get some input here, I guess no one is loading Retumbo and long loads. Guess just load the thing like I would a 308 or 243 and figure out where I find pressure signs and where the velocity ends up as long as it shoots well run with it. Later,

Kirk

its just a decision you have to be comfortable with. the guy posting above said he hit 3000fps with a 215 and h1000 I maxed out with a 212eldx at 2860fps and 71.5grs before pressure signs at 73.5gr...just depends. (i backed down the charge for the accuracy node)
If you want to run a later test nice and slow and see if you can get it up...and YOU KNOW WHAT YOU ARE DOING, then sure, bump it up. If you dont really care about the extra fps and would like to save your brass and barrel...and maybe your gun then just leave it. The rule kind of applys to all powders and not just retumbo. I go over max charge with my .308 using varget, no pressure signs, works fine in my 20" barrel, i thought it important to get the extra vel, so i did.

 

[Ksmirk]

This rifle has a 28" barrel.

I'm all about accuracy over velocity! my 243 I'm just running 3009fps so I'm not too worried if I have to click the scope a couple more but I sure am curious as to where I'll hit pressure just seems to be rather fast for that bullet weight.

I was hoping some folks were still shooting Retumbo to sorta compare notes with but guess I'll just load like I do for all the rifles and figure out the best result..... I guess if it wants to be fast then can't argue with what the rifle wants. Thanks for the replies fella's! Later,

Kirk

 

[3stooge]

Well, the 28" barrel does explain a little bit as to why the vel is so high. But, with that said, it still seems like with that velocity you are likely over pressure. According to Quickload, it looks like max pressure would occur somewhere around 3,050 fps.

Quickload did not match the velocity you are getting. It predicted 2,915 fps for your 81.5 gr load. Now, I just used an assumed water capacity for your brass so if the brass has less volume than assumed. It seems that your powder might have a burn rate higher than the default in Quickload. Even a 5% increase in burn rate and 82.3 gr charge is supposed to get 3,007 fps at just about max pressure.

I hope this helps. If it were me, I think I'd look for accuracy below your 81.5 gr load.

 

[can1010]

I read this yesterday and ran my case capacity and adjusted burn rate for my lot of powder and took a guess at barrel length of 30 inches and you are at max pressure to get that speed. today I see you only 28inch barrel and not having enough info to use QL safely BE CAREFUL.

 

[Ksmirk]

Measured 3 cases and came up with 96.4, 94.3, 95.4 for an average of 95.36 water cap full to top of neck.
COAL 3.742"
Berger PN: 30429

Just because I took a magnifying glass and inspected the bases as I've run into a couple before that you could hardly see anything but could never find anything, primers looked great, cases after I measured were still under spec per SAMMI but the were once fired so don't really find that information helpful. Maybe it's just one of those things?

Fella's I do appreciate the help! I was going to purchase QL but the amount of times I'd use it I just couldn't justify the cost..... sorta wish I had it now so I'd not have to bother folks. Later,

Kirk

 

[3stooge]

I'm fairly new to QL, so take this info with skepticism:

I adjusted the Ba for Retumbo, and adjusted the shot start up pressure to try to match your velocity and the way I'm seeing it you are looking at around 70,000 psi in order to get to 3060 fps. It looks like max should be around 79.0 gr and 2980 fps.

How confident are you in your chronograph reading?