Home Forums Hunting & Shooting Elk Hunting 300 weatherby mag reloading question

I have a friend who bought a new Mark V Weatherby in 300 weatherby mag. The only load it shoots worth a hoot is a factory 165 grain ballistic tip. So he bought a set of dies and I have it and am trying to get a good load. I have never seen a rifle with so much free bore. What are some tips to get the proper seating depth?? Anything close to the lands and the bullet in not seated into the case very much, at least with 165's.

My 300 Weatherby also has long freebore. I think that the cartridge is much more effective with 180 gr. bullets. I've had some success using 180 Accubonds loaded to the maximum OAL that the magazine will accept and still feed reliably. This bullet in my Accumark has consistently grouped five rounds in about four inches at 358yds. Not stellar accuracy, but acceptable for its intended use.

I've had a few Weatherby's and loaded for a few others. I ignored the freebore and loaded for the magazine. You wouldn't believe how accurate the 7mm Wea is. One .340 was regularly 3/4" for three 210 Partitions. Another 340 was only good for 1" with three 250 Partitions.

Thanks guys will give that a try as soon as these winds slow down. FYI I tried 180s and the 165's grouped better. But will try some of each loaded to the mag length.

I believe all the weatherby rounds are freebored chambers, not sure about mark Vs in std calibers. My experience is that the wby factory rounds shoot so well most of the time, the only reason to reload is for cheaper shooting at the range. My 300 is a little more finicky though, haven't found a load to equal factory 180s that get an inch if I'm good that day or 1/1/2-2 if I,m too quick on the trigger. A 257 with 120 NPs and a 340 with 250 NPs are under an inch any day of the week. All at 100 yds of course. So basically I gave up and use factory stuff to hunt and just do a little reloading for the bench. I would follow ringman's advice and load for the magazine and smooth feeding.

This gun does not like any factory stuff except the 165 ballistic tips from weatherby. He has tried LOTS of factory weatherby rounds, more than I would have I know that, those things are not cheap

Lots of freebore is SAAMI specs. Don't worry about it.

My 300 likes IMR 7828 with 150gr TTSX and 180gr Accubonds. The 150gr load has a high ES though.

I've also had good results with 180gr TSX + H4831 and 200gr Accubond + Retumbo.

I'd try the 7828/180 Accubond load first. If that doesn't work, try some H1000.

180gr Accubond will shoot through elk from most angles.

Also, Barnes like to jump to the lands, so be sure to try some if other bullets don't work.

So far this rifle does not like 7828ssc. It seems to like IMR 4831. I am very familiar with loading barnes bullets. Just have never jumped a bullet this far before. Going to cut a groove in a empty and see just how much freeborn there really is, don't have a OAL case for my tool in this caliber.

If you are going to reload the Weatherby calibers it's helpful to understand the case design as they are slightly different than standard calibers.

The Weatherby freebore is a critical design factor that enables high velocity without excess pressure spikes.

In other words, it's there for a reason.

Weatherby factory ammo is loaded to the max and is unsafe to fire in a rifle that doesn't have the freebore present. Any published load data takes that factor into consideration.

The point is that loading to the lands is not an option in a Weatherby factory rifle, so just duplicate factory OAL specs or load to mag length and save time and barrel wear.

I also don't push the Weatherby to max, as most Weatherby brass available is on the soft side. 60k is my personal max chamber pressure. That's more than enough for any application and allows the primer pockets to survive through a few loadings.

In my Weatherby the 200 gr Accubond works well across the board. The 165gr bullets match-up well in a 308 or 30-06, but I don't waste the case capacity and barrel life with a bullet lighter than 180 grains for full power loads, unless I'm loading mono bullets.

Weatherby used to use IMR 7828 in their factory loads. I don't know if that is still the case, but H-1000 is an excellent powder for the Weatherby.

I would start and end with a 180gr. pill like the partition or accubond and 84gr. of IMR 7828. If your rifle doesn't like that weight of bullet or that powder, it needs to get sent down the road... Every 300 WBY I've loaded for loved a stiff charge of IMR 7828 and 180gr. pills... Also don't worry about the freebore. WBY rifles are that way, they can still be made to shoot lights out..

Forget about the freebore. It's there and there nothing you can do about it.

300 Wby freebore is .3084 diameter and .378 long. Hard to reach the lands with most any bullet. Load to mag length and carry on.

All of this is true, but what I want to know is, is there anything better for elk hunting?

thats all taken care of in another post

Tom338,

I load for my .300 Wby, using Barnes 165 gr. TSX or TTSX, ahead of RL22. I seat the bullets with the case mouth in the center of the top groove, and like many others who load these bullets, I get excellent accuracy and velocity.

3.56" overall length with the 180 TTSX and a max charge of 7828ssc. It shoots very well.

I did try 3.55" and 3.57" and they were appreciably larger groups.

I've noticed a peculiar phenomenon with 300 mags over the years. Most of the ones I've shot, if they liked a 165, they'd also like a 200, but not a 180.

I'd try a 180 and if it didn't care for it, I knew I had a 165/200 rifle.

Can't explain why...but I've noticed it too many times to ignore it. May or may otherwise apply with your Wby. Best of luck!

This is going to be one of "those" guns.. does not seem to be liking anything. Barrel really heats up fast also, wish I had this gun this winter to work loads, cooler. Seems to hate 180 grain bullets, no mater where seated or which powder. Have another 7 sets of bullets loaded and will see on sunday what happens. I have tried 23 different variations so far, hmmmm.

Try some IMR4350 or RL22.

Yeah I know....temp sensitive.

But try them.