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.

I got lucky.

The first round fired I from my 300 Wby was a 180 Hornady over IMR 4350. It was a load recommendation that I got from Roy Weatherby, but I dropped it down a few grains to start.

The loads Roy gave me were...let's say...enthusiastic.

It shot around an inch and that was already better than the factory target that came with the rifle, so I stopped right there and went hunting.

The good news about doing such an extensive load work-up for a 300 Wby is that the barrel will get shot-out faster and the rifle can then be re-barreled with a tube that will shoot just about any bullet/load combo into tiny little groups a lot sooner.

Win/Win

Its sure looking that way

Had one 300 that didn't like anything also. Tried all the super accurate boat tails and was about to give up and then discovered it wanted flat base bullets all along. Might try some Hornady Interlocks or Sierra's and see what happens. Always enjoyed good accuracy with the Hornadys.

Thanks Godogs57, I happen to have a box and have not tried that yet, will give them a try

In my Mark V I load:

Fed 215
84.0gr. RL-22
168gr. TTSX

I tried alot of different powders in mine with 168 and 180gr bullets and settled on the above load. Makes elk get dead real fast!

God luck with yours,

Elk Country

General Rule:

Whenever one of these bad ass magnums junks out with the real slow burners, go the other way and work to max with a faster burning "slow" powder,like IMR4350.

OR

A double base like R22.

I don't know why but results are often satisfactory and they will group better than the real slow burners. I think it's harmonics and efficient burn but that's a half assed guess on my part. I no longer worry about "why" because I have seen it a few times too often.

This rifle is going to be a fancy fence post real soon. Tried IMR4350, IMR 4821 reg and SC. IMR 7828SSC, Reloader 22, H3450. 150, 165, 180 grain bullets from hornady, barnes, nosler. Today shooting 4 shots of a test load, three out of 4 were 1/2 inch and the 4th 1.23-1.50 apart, nothing consistent when the flyer would show up. There were 2 very good shooters at the range today who do extensive reloading, they looked and just said, oh its one of those guns. Brass is all sized, trimmed and has the same number of shots the them, (2). oh and using CCI 250 mag primers. Any other ideas??

Yeah...

First, accept the fact that all rifles will not be consistent tack drivers/tight groupers...especially those chambered for hot, blown out 300 mags in light tubes with factory assembly.

Next, I would take what looks like your best 2-3 powder/bullet combos based on your 100 yard work. Load up 9-10 of each. Slowly fire 3 shot groups at 300-400-500 yards.get off 100 yard 3 shot groups because they lie a lot.

Watch for 1st shot consistency and POI. Can it hold MOA through several strings of fire? Put first shot where it needs to go from cold barrel?

Working with too many combos hoping for magic results can lead to waives of disappointment.

But watch what happens at longer distances. It may tell a different story. And be realistic of what you expect from the rifle. It is intended for killing BG, not prairie dogs.

If all else fails,maybe time to give it to a smith for tuning/bedding/ rebarrel. That is part of life with rifles.

Good post Bob. However, you left out one of the most important things to consider: Be realistic with your shooting ability. Shooting magnums accurately is harder for some guys than others...... I have a friend like this. He's perfectly content with shooting his 22-250 and 270, but when it came to shooting his 338 win mag, that was a different story all together. I hate to pull this taget out again, but it needs to be a consideration. I'd also point out that if a guy can't hit the broad side of a barn at 100 yards, things aren't going to get much better at longer distances. Just a thunk:

This is when I dialed in the scope for Troy:


His group can be seen in the upper left hand side of the target. Close-up of his group:


As you can see, the rifle was fully capable of "sub moa" accuracy. But with a different shooter, the shooter was not capable of it.....

bsa: I never go there...

I assume shooter and rifle are compatible.

But I too have weened a friend or two off a 300 Weatherby, put them on a 270 and watched good things happen at the 300 yard line. It was in prep for an Alberta deer hunt and the improvement was something to see.

But I assume for these discussions guys know their recoil tolerances.

Some guys don't my friend. I have some friends that are too quick to say their rifles are a POS and don't shoot well... Just saying it happens more than I care to admit...

I shoot a 338 win mag, have for 35 years...Just got a new one and just got a load figured for it. I can consistently get 0.60 in groups with it. I have a 7MM rem mag and it shoots even better, not because its smaller, it has a custom barrel that I put on it. Bet 5 shot out of it, 0.19 @ 100 yards. Once in a while this 300 weatherby will shoot a 0.75-0.60 group, but you can never repeat it with the same load. It is never consistant with where the 1st bullet goes either. I have waited 10 minutes in-between shots so the barrel heat won't be a factor. Played again with it this afternoon. And I'm done with it.

Tom sounds like you have been around the horn! Trip it life is short!

Its very frustrating. This rifle should shoot. But I guess you don't always get what you pay for. But as with ALL things made, some don't always live up to expectations.

The 300 Wby is a hassle free round to load in my experience, but since you are struggling so much with this rifle here's an idea...

The first thing I would do before going any farther is to replace the scope with one that is known to be good-to-go.

My formula for the 300 Weatherby is this:

Weatherby Brass
Fed 215
200 Accubond
H-4350, H-4831 or H-1000
OAL min 1/16 under mag length

With groups just under an inch

Once fired Weatherby Brass headspaced to the shoulder (not the belt)

H-4350 seems to shoot well at any pressure but all the above powders work well at 60k psi or 50k cup.

All this and having a reasonable expectation of accuracy goals.

One should keep in mind that all bullets are not created equal...

Not all otherwise excellent hunting bullets are capable of better than 1 1/2" groups at the bench. The only true measure of a rifle or load potential is with a match-grade bullet. Any group 1" or thereabouts sub-moa load with a standard hunting bullet is good-to-go.

Of course my rifle is steel bedded and the stock fits me well.

I shoot 5 round groups in the light barreled Mark 5, but rapid or real slow fire, the barrel drops them in.

You might need to do your serious range testing from a barrel that hasn't seen a cleaning rod for several boxes of ammo, or make sure that a squeaky clean bore is completely degreased with brake cleaner and alcohol as the final step.

Any residual oils can wreak havoc with grouping for a box or two of ammo until it gets shot out of the bore.

Also, some barrels need to copper-up a little before they settle down.

I'm just talking generally here, because I generally utilize moly or hBn and never clean the barrel with normal solvent or oil.

On rifles that I do, I utilize the brake cleaner before heading out.

Tom but aren't those Weatherby rifles built to a 1.5 MOA guarantee?

If so sounds like you are already "there". Other than wallow around with loads, or rebbarel or re bed, I don't know what else to do. re barrel? rebed?

Send it out for professional TLC?

One idea I don't think has been shared: Have you thought about letting a friend (with proven shooting skills) shoot the rifle to see how it shoots for them?

At least by doing that, you could prove or disprove possible "excessive operator headspace".

I've seen me do that before...on both sides of the argument! Hope you find a solution.

Yes, it does have a 1 1/2 inch guarantee. Its not my rifle, loading for my hunting partner. I'm not sure what he is going to do with it. All I know is it's beyond my ability to do anymore. I do know if it was mine it would go down the road. I will not have a rifle that groups this badly. This was supposed to be his long range rifle, max 500 yards. I would not take a shot at an animal with this rifle at that range, not ethical. Oh well, I have learned a lot while messing with this. Thank you everyone who chimed in and tried to help. I always can learn something new to look for or re check.

My 300Wby had a bad vertical string problem no matter what combo I tried. I free floated the barrel and nothing changed. I took the factory synthetic off and bought a used Accumark stock from the classified, bedded the action and torqued everything down. First group out of the gate with 84.5grs IMR7828 and 180 Nosler Ballistic Tips was under 1".

I've owned many Weatherby's perhaps 10 in 300 WBY. I reload and most were good for cold bbl 3 shot group. My FIL left his at my house. It was terrific. Killed Elk with it.

He kept saying he was going to pick it up, never did and when his kids picked out 3 things for the will my wife chose the WBY. She lets me borrow it.

Knowing the WBY handles recoil better that the WIN or REM in 300, owned them, I found quite a few
I could trade into. I wanted one that shot as good as my FIL's, a few were close. I am talking German ones.

If they were not close they went out the trade door.

I had one that was in 26" It shot every thing bad. Factory and my reloads that were super in other ones.

I was going to quickly move it then decided to pull the action, There was pressure on one side of the bbl pretty far up.

I relieved this and it shot much better, it was not a keeper but shot acceptable.

I found a beautiful blond wood German one with the 24" bbl in a small LGS. It had a crack coming down the wrist. He could not sell it. Got it super right.

I fixed the crack, it was not noticeable, glass bedded the action and that was one great shooting little blonde lady.

I would also look for cracks in the wood around the trigger when I pulled the action.

Make sure the action screws are tightened correctly.

I've fixed quite a few WBY stocks. They have nice wood and are very thin. I would not buy a WBY if the swirls continue into the wrist and past the front of the action.

That pretty wood is the most brittle wood ever.

Sorry to hear that. Sounds like you are a great shot too, so I'd be looking at the rifle in question and loads as well. Too bad there wasn't some quick cure. As long as you have crossed every T and dotted every i, the only other option is to send it down the road and let someone else play around with it. I'm really surprised that it didn't perform well with IMR 7828 and 180gr. pills. Usually they dote on a real stiff load. I remember mine was loaded so hot that I thought of a bowling ball coming out of the barrel at mach 2 speeds... It had a certain familiar sound to it....

bsa1917hunter, I tried 7828 in everything from 159-180. I use that powder in both my 7mm Rem mags. I was actually one of the poorest grouping powders/load combos that were tried in this rifle. I thought sure that the slow burning powder would settle this thing right in there. For one reason or another the best groups with this rifle were always with IMR 4831. And by a wide margin the best. 7828 made shotgun type patterns. I will be thinking about this rifle for a while..... probably not good thoughts

Quicker powders frequently show better grouping than the slower powders in rifles that need some TLC IME.

Sounds to me like this rifle could use some stock work or other mechanical improvement.

When you have to run through a variety of powders and bullets to find a couple of things that shoot it is usually the rifle tat needs the work.

Fix the rifle first; the loads will fall into place.

This, get someone who knows what they doing to bed and float it. I would bet that you will find evidence of it moving around in the stock.

How well does the 155 Scenar work in the .300? Or would I be better off to try the 180's & heavier?

No

I like the way Bob thinks/feels about this. I always attack the mechanical aspects first before even trying to develop a load for a rifle. These are the things I'd check/correct to be certain it's not a mechanical problem vs. a bad barrel or bad loads:

1. Proper glass bedding.
2. Float the barrel, pressure point, or full length bed the barrel. Which one does the rifle prefer???
3. Mounts need to be loctited down to the receiver and torqued down. It doesn't hurt to even glass bed the mounts to the receiver. It adds structural integrity to the mounting system.
4. Rings should be checked for axial alignment to the bore. They should also be dialed in with an alignment tool. If rings are not in perfect alignment, lap in rings.
5. Torque action screws to factory specs.
6. Fine tune trigger. Should be glass smooth and break clean. I like all of my hunting rifles to be set around 2.5 pounds.
7. USE A "PROVEN" SCOPE. I can't stress this enough!!!!
8. Check to make sure mag box is not binding.
9. Be sure crown is in good shape.


Now with your handloads:

1. Adjust sizing die so it minimally sizes your cases. .003" shoulder bump back works great, even on belted cases.
2. Adjust seater die for minimal run-out (less than .004"). This can be achieved, even with run of the mill RCBS FL die set.
3. Check loads for TIR. As stated above, .004" and less is preferable for accurate hunting loads.
4. Use a chronograph. Check ES and SD's. These should be low and consistent.


Also keep in mind that the 300 WBY is prone to washing out the throat (erosion) and wearing the bore, especially if you push them like some of us have been known to do. I remember reading somewhere that accuracy degrades even after 1,000 rounds of hot 300 WBY loads. I've seen this first hand. My 300 wby went from shooting 1/2" groups to 1 1/4" groups after 1,000 rounds.

I'll reiterate what Bob said, fix the mechanicals first, then focus on the loads. Good luck with it. Hopefully it just needs to be glass bed or re-glass bed, experiment with barrel pressure points, a little trigger work, etc. etc...

Never tried one at that speed, but 3500 fps might be pushing it.

I guess I've been lucky, my Mark V 300 has shot everything I've thrown at it well.

I would send the rifle back to Weatherby and let them sort it out.

We had a similar experience with one of the new POS budget rifles from Remington in 30-06. My cousin claimed that I could straighten the gun out for him based on what he had seen me do with other rifles. Well 3 scopes, 3 mounts and many loads later he gave it back to his freind and told him to sell the rifle it wasn't ever going to be worth the $100 he paid for it.

Easy to understand a cheap crummy Remington than a better constructed Weatherby but either way it is frustrating.

I'm with BSA, Bob and others. Seems like your just burning through pounds of expensive bullets and powder. Usually if 7828 and a decent 180 won't shoot then the rifles probably suspect.

My sons 300 needed to have a pressure point added in order to be consistent. Now it shoots so darned well it's amazing. Took a couple hours and some Marine Tex but it's good.

Well....this one is obviously well behaved


If you have to sift through 5 powders, and 47 bullets,and magic incantations to get a rifle to shoot well, it has issues.

Trip it or fix it.......but good grouping does not start with "Magic Loads".That's like trying to build a house on a crooked foundation.

Amazing how long it takes people to figure that out.

My 300 Mark V Deluxe shot 3/4" groups out of the box with the cheap Weatherby 180s. I don't think I've ever shot a bad group with it.

I settled on 180 NPTs over 7828 at a touch over 3250


I'm with Bob on this.

GODOG ~
Interesting I replied to an Elk post about this subject.
I have experienced just as you described! I have a few
one shot kills with 300 Wby but 180s just do not group great.
I do not have as much confidence as my 270 WBY. Both my
Wbys are in custom 700 actions. Love the 300 hit and seek
to tighten it for long pokes. I am a beginner
reloader and like the ballistic chart of 190s and 200s in fact
they should mimic the arc of my 270 Wby with 140s. I have accubonds
and Nosler 190 Long range bullets but have not loaded them yet.
Do you have any other bullet and powder suggestions?

I use the TTSX in my Weatherby's loaded to factory length. The dont mind the free bore.

There's part of the issue right there perhaps. Quit at three shots. A fourth round out of a blowtorch like Weatherby calibers are will skew your results. Also, try this formula that has worked in ALL the 300s I've owned;

Norma/ Weatherby brass
F-215 Match primers
80.5gr RL 22 (3250 in my rifles)
180gr TTSX seated to the crimping cannelure.

If a three shot group is not well under MOA, the rifle is the issue.

Or the scope.

84.5 gr Imr 7828 with 180's has been the go to load in the four 300 Wby's I load for.