338-300 wsm questions.

[Skimbleshanks]

Starting load development for my 338-300wsm. Its build on a Rem 700 sa with a Wyatts mag box and 27or 28" Rock Creek barrel. I have been loading 59 grains of Varget behind a 225 Accubond in Nosler 325 wsm brass with a WLR primer. 2752 fps. This load is HOTT in my rifle. Its the load that the smith worked up but it is showing more pressure signs than I feel comfortable with. Ejector swipes, stiff bolt lift, primer cratering and 2 popped primers in the last 28 rounds fired. Needless to say im pulling the remaining ammo down and dropping the powder charge by 5% at least and will use these components for fouling the barrel after a cleaning. The Nosler brass is toast now anyway. A shame as it is a 3 holes touching at 100 kind of load.

I just recieved 100 pieces of Winchester 300 WSM brass and my inability to find the 225 accubond lead me to pick up a box of 100 Hornady 230 ELD-X. Probably sticking with Varget and WLR primers though im open to powder suggestions as well.

My first question is the brass. Should I anneal it before I neck up or is Win brass alerady annealed?

Next question. The ELD-X does it have a preferred seating depth? Do they typically shoot well with a standard jump distance?

If 59 grains of Varget is over max in this rifle with a 225 what would be a reasonable possible max by switching to a 5 grain heavier bullet?

I understand im changing this load a lot by switching brass and bullet and that I need to work it back up. Just looking for a good starting place I guess.

 

[Jerry M]

That is a big case for Varget you may have better luck with a slower powder.

Good Luck

Jerry

 

[AZShooter]

I strongly suggest you switch to a slower burning powder. Something in the 4350-4831 range. FYI RL-17 (similar burn to H4350) was made for this case. I got 2770 fps from the smaller 338 RCM case and 61 gr of RL-17 with a 22" barrel. You should be able to improve on that.

 

[J E Custom]

Starting load development for my 338-300wsm. Its build on a Rem 700 sa with a Wyatts mag box and 27or 28" Rock Creek barrel. I have been loading 59 grains of Varget behind a 225 Accubond in Nosler 325 wsm brass with a WLR primer. 2752 fps. This load is HOTT in my rifle. Its the load that the smith worked up but it is showing more pressure signs than I feel comfortable with. Ejector swipes, stiff bolt lift, primer cratering and 2 popped primers in the last 28 rounds fired. Needless to say im pulling the remaining ammo down and dropping the powder charge by 5% at least and will use these components for fouling the barrel after a cleaning. The Nosler brass is toast now anyway. A shame as it is a 3 holes touching at 100 kind of load.

I just recieved 100 pieces of Winchester 300 WSM brass and my inability to find the 225 accubond lead me to pick up a box of 100 Hornady 230 ELD-X. Probably sticking with Varget and WLR primers though im open to powder suggestions as well.

My first question is the brass. Should I anneal it before I neck up or is Win brass alerady annealed?

Next question. The ELD-X does it have a preferred seating depth? Do they typically shoot well with a standard jump distance?

If 59 grains of Varget is over max in this rifle with a 225 what would be a reasonable possible max by switching to a 5 grain heavier bullet?

I understand im changing this load a lot by switching brass and bullet and that I need to work it back up. Just looking for a good starting place I guess.

53.0 grains of Varget will get you only 2600+ ft/sec with the 225 at reasonable pressures. I have found that H414 works better, and for the case capacity, a 200 grain works much better and makes an easy 2800 ft/sec.

I like the 225 Accubond's for tough game and load both the 200's and the 225's.
for most hunting the extra velocity makes up for the bullet BC's.

Also Winchester brass is normally very soft and doesn't need annealing on the first firing.

J E CUSTOM

 

[Skimbleshanks]

I have a pound of h4831sc, and I need more h4350 for my 30-06 any way, so will have that on hand as well. If h414 or
Rl-17 would be a better choice I can pick some up as well. Seems like h4831sc might be a bit slow but might work well for the barrel length and heavy bullets.

 

[J E Custom]

The problem with the short mags is their case capacity is around 60 to 65 grains max and the 338 Win Mag is close to 10 more grains capacity. so it is very hard for the short mags to even come close to the Win Mag with heavy bullets unless you over pressure them.

I recommend 90 to 100 % case density on any cartridge with powder that Meets SAMMI pressures at 100% densities. Any more pressures at 100% means the powder is to fast.
any less and it is slow. With a drop tube, i can get 103 or 104% densities and still be within range with reasonable pressures.

Even though most re loading manuals are conservative, they can help in choosing the best powder for that cartridge if you study the velocity produced with each type and weight of powder and at what point it becomes compressed.

J E CUSTOM

 

[Skimbleshanks]

Looks like berger did some load work with their 250. H4350 seems like the powder to try first. I already use it for other cartridges so thats nice. Not trying to reach win mag levels but really want to be between what the 338-06 and 338 win mag can do. Might pick up some H414 incase the H4350 doesnt work out. Thats a spherical powder isnt it? Is it temp sensitive?

 

[Forcedoutage]

RL 17. Is also check freebore. As mentioned above.

 

[Beachnmountains]

Hi Skimbleshanks,

That's really cool you have a 338 WSM. Starting to see more and more of them. Funny you showed that Berger document. It was one I would think they would never publish with the slower than typeical speeds. SHHHHH, it doesnt shoot those bullets well!!

Personal favorite is RL17. I have loaded some light bullets for giggles, but 225gr bullets I believe are the way to go for balance of BC and speed. My barrels are a lot shorter than yours. RL17 burns quickly so you maybe able to go to different powder and definetly a compressed load if you don't mind.

My checklist on powders, burning it all is pretty high up there.

 

[LongBomber]

Whats your loaded oal? Did the smith set it up to magazine feed at 2.86" oal?

 

[Skimbleshanks]

Whats your loaded oal? Did the smith set it up to magazine feed at 2.86" oal?

2.975" is my oal.

Going to get a chamber cast done soon to know exactly what im working with.

 

[LongBomber]

2.975" is my oal.

Going to get a chamber cast done soon to know exactly what im working with.

Been thinking about building one that I will throat long and run it single feed. I want to seat a couple of the high bc bullets out where I want them and see if I can come up with a good length to have the chamber cut to.