Just picked up a Whitworth/MK X with after-mark 375 H&H barrel

I already have a 375 so want to convert this one, I'm leaning towards 300 H&H but would appreciate other suggestions

458 lott

22WRF, the seller think it was a Douglas but not sure, he bought it as a barreled action

Not sure what I'll do with it but if I decide to sell it I'll send you a PM


Jeff, I don't need a DGR but if I went bigger I'd really like a 404 Jeff

Could it be converted to 35 Whelen? Would I need a spacer in Mag box?

The bolt face is too big for the Whelen. But a 358 Norma Mag would do just fine. 416 Rem would drop right in too. Any of the Ultra mags and 404 Jeffery based cases would work too but might need some work to feed properly.

As I've always wanted one, I'll second your thoughts on a 300 H&H.

quote:

Could it be converted to 35 Whelen? Would I need a spacer in Mag box?

If you really want a 35 Whelen I bet any number of people would swap a MKX std action for the long. Probably with some boot $$ as well.

I have a 358Norma in a std length FN and love it. Does everything my Whelen did plus some. I think it would be a little short for the longer box. Might need a spacer or at least the bullets seated as long as possible.

Any of the H&H length magnums like the 300H&H, Lott, or 8mm mag based like the STWs would work as a drop in.

A 300 H&H would be a great companion rifle to your 375. One of my next projects will be a 300Holland.

Rich

First option is to ream to .375 Weatherby. Same caliber but a little more horsepower.

The .300 H&H would be an excellent choice.

Like everyone else, the first thought I had when reading your title was a 300 H&H.

Besides, if you wanted a 35 Whelen it really needs to be on an 03 action, not a 98 IMHO. <G>

Anybody got a 300 H&H take-off barrel that would fit a MK X?

I'd advise against the 300 H & H as it is overlong...giving bullet seating issues. Better maybe with a 300 Win Mag or indeed a 308 Norma?

quote:

Originally posted by enfieldspares:
I'd advise against the 300 H & H as it is overlong...giving bullet seating issues. Better maybe with a 300 Win Mag or indeed a 308 Norma?

300 H&H max OAL - 3.665"
375 H&H max OAL - 3.600"

quote:

300 H&H max OAL - 3.665"
375 H&H max OAL - 3.600"

Just checked two sources I had close to the PC both show the 300H&H as 3.6"

quote:

Originally posted by jeffeosso:
458 lott

+1

Keith

quote:

Originally posted by ramrod340:

quote:

300 H&H max OAL - 3.665"
375 H&H max OAL - 3.600"

Just checked two sources I had close to the PC both show the 300H&H as 3.6"

The dimensions I posted came from Sierra's 50th.

quote:

The dimensions I posted came from Sierra's 50th.

Mine were Nosler Four and Loadtech software.

If it handles a 375 it should handle the 300 just as well.

What are you looking to do with this gun? That helps on deciding what to do with it. If you're possibly interested in a big bore wildcat, which you barrel and action would be perfect for..go to the wildcat forum and look at the poor mans 404 thread!

22 WRF

How does the 300 Win Mag cycle in the long action?

Craigster - Checked all my manuals, only Sierra listed COL over 3.60, wonder if it is a misprint

quote:

How does the 300 Win Mag cycle in the long action

Never tried this combination. If the feed rails are straight from the factory it would probably work. Tried feed a 7mag in an STW it worked fine for the first rd. When I shoved the rd forward like it would be after recoil and it was less than perfect.

Take a 180 gr in a 300mag and seat it out to 3.53" and you sill have full contact in the neck. Longer OAL might help feeding.

Nothing wrong with a 300wmag. But to me if I had a long magnum action it would be settling. Heck bet if you watched you could trade the action for a MKX already in 300wmag and save yourself the trouble.

Thanks Paul

I'm looking at the idea you had about converting 30-06 barrel to 300 H&H

quote:

Originally posted by Abob:
22 WRF

How does the 300 Win Mag cycle in the long action?

Craigster - Checked all my manuals, only Sierra listed COL over 3.60, wonder if it is a misprint

Could very well be, Lyman says 3.6 also, my Hodgdon and Speer just show max case length, no max OAL.

quote:

Originally posted by ramrod340:

quote:

The dimensions I posted came from Sierra's 50th.

Mine were Nosler Four and Loadtech software.

Hornady says 3.665
Lee says 3.6

My Hornady #7, Nosler #6 & Speer (latest) say 3.60

Barnes Bullets website reloading data has different COAL for different bullets but none are over 3.60

Go figure

300 H&H
340 WBY
358 STA
416 Rem
458 Lott

Might as well use the full length of the magnum action. Otherwise I would also throw in the 358 Norma. Lou

I think I should have put my comment about OAL better. What I meant was that by being "overlong" is that you can't use bullets seated as far out as can be done on a 300 Winchester Magnum.

Thus on Holland and Holland made 300 H & H chambered rifles you usually have that horrible "cut" or "notch" on the front receiver ring to enable the cartridges to be loaded from the top.

With bullets seated further into the case or bullets with a flat tip (as most H & H factory loads used to be) it isn't a problem nor with 375 H & H which uses a "shorter" bullet.

But for a longer heavier bullet that you want to seat "out" it may be...but if you ignore the manuals and use the actual physical size of the action on your Mark X action you should get this extra OAL potential if chambered to 300 Winchester Magnum or 308 Norma Magnum?

So the

abob, I have a Mk X barrel in 30-06 that I bought for the same conversion but found a 300 H&H so have it as a spare. Let me know if you'd like to buy it. No sights, bluing looks perfect. Bob

quote:

But for a longer heavier bullet that you want to seat "out" it may be...but if you ignore the manuals and use the actual physical size of the action on your Mark X action you should get this extra OAL potential if chambered to 300 Winchester Magnum or 308 Norma Magnum?

I agree if you are looking at max performance since the 300wmag and 308Norma have the same or even slightly higher case capacity loaded long you will increase the net even more. But heck if you want powder capcity simply chamber for the 300Wby and add 14% gross. Since the OAL of the Wby is 3.56 you even seat the bullet out further.

I've had the 300Wmag, have a 308Norma and loaded for a 300Wby. Other than kick hard and more blast I never saw what the WBY did over the other two in the real hunting world. Looking at those can't see what they would do the 300H&H wouldn't do.

As I said earlier cheapest thing sell the long action and buy a used 300Wmag. To me the 300wmag, 300Wby and 308 Norma just doesn't carry the charm of the 300H&H. What you kill with them will never know the difference.

quote:

abob, I have a Mk X barrel in 30-06 that I bought for the same conversion but found a 300 H&H so have it as a spare. Let me know if you'd like to buy it. No sights, bluing looks perfect. Bob

Ask and you will receive.

Paul, you are the "Man"

bobc - PM sent

bobc- PM sent