Terry; don't do this to me,It's just not fair but
no it will have to be the 300 H&H.

P.S. How accurate is your rifle?

Regards Martin

Martin,
You will definitely have to rebarrel. To cut all the .300 Winchester chamber would take a lot of the cylinder section from the exising barrel. Have not cranked out the numbers but it is not feasible to save the old barrel and rechamber to .300 H&H

Now Martin, One thing you gotta know is I did something most would consider taboo. common practice is to put a 1in10" twist barrel on a rifle like this, but I went with a 1in12". I've shoot 168gr SMK's .50 @ 100yds with a stout dose of H4350. For my hunting loads I've been using Hornaday 180gr RN's and they shoot MOA (occasionally better) all day. This was the bullet I had in mind when I had this rifle built and that's why the smith suggested to use a 1in12" twist, it was a good call on his part.



The .338/.300H&H was just an idea I'v had for a long time. It serves no practical purpass and I have yet to get past the "dummy" cartridge stage.



Hey Chic, I guess we all left the new barrel part out didn't we



Terry

One might say that all cartridges are good. I have both of these and the 300 WM, while not having character, is better with both factory loads or handloads.

There are way more factory loads available for the 300 WM and the case holds it's headspace after the first shot. The 8 degree shoulder on the 300 HH does not.

The thing to do is to have the magazine box lengthened on the 300 WM and even have the throat cut forward a little. You will be able to use the existing barrel and shoot factory loads if you want to.

My M70 Classic SG has at least a 3.4" magazine box and it holds most 180 gr bullets.

Just bought a LH M70 Winch LT in 300WM for a conversion to 300 H&H.
I am not a 30 cal fan but I think it would complement my 375 (LH SE).
We took some measurements from a pre 64 300H&H and a pre 64 30.06.
The only diff we can see is the mag box and some cuts in the front and rear action rings.
The action on the S.E. seems 1/8" longer.
I phoned the Winch tech. and he tells me it would work.

The question did anybody do a conversion like this and if so what's all involved other than rebarreling

Regards Martin

Yes it can be done but make sure it is done right. First order a follower and box from Western gun Parts or Brownells for the 375 SE, or better yet from Blackburn. Then find the right gunsmith for the job. I just had Bill Leeper convert a LH model 70 action that was built around the 7MM rem mag to 375 like dimensions.

First of all, the outside dimensions of your 300 and 375 are the same. The modifications that are needed are: the rear bridge needs to be milled rearward, so the loading port dimensions are the same as your SE, the bolt stop and ejector need to be milled to SE dimensions, the action behinfd the box needs to be modified (you can see the difference if you look at your two rifles side by side), the rails need to be modified at the rear, and a new forward scope mounting hole on the rear bridge will need to be added.

Get a set of dial callipers, compare the two actions, and it is apparent what modifications are required.

Chuck

If it is just the action you are talking about then yes it will work fine. Unless I missed something you can't got from a 300WM to the 300H&H. Back to the action when I go the long cases I simply contact Winchester and buy a longer magazine and shorter ejector and bolt stop. Other option is to take the spacer out of the back of the magazine and shorten the ejector and stop.

Just drill out the spacer in the magazine box or replace it, replace the follower with one made for a .375H&H If you get it directly from Wincnchester it won't need to be fitted. Cut the boltstop back about .10" if I remember correctly and you're in buisness. You could go the extra steps but why? It will preform flawlessly without them.



Mine started out life as a 7mag. Works perfectly.



Terry

I like things done right the first time.

Chuck

things are done right on mine, you just want to make things expensive that's all.



Terry

Thanks for the reply gents.
I don't have the gun jet,just ordered it yesterday.
I was just a little worried about buying a $1000. rifle to find out that my plan would not work and god forbid ending up with a 300 WM .
I to would want it done right but there is no need to spend more than we will have to ether.
Yes Bill did a 350 Rem for me not to long ago,since the project involves rebarreling I will have to talk to him anyway.

Chuck;how come the rail modification,both cart.heads are the same are they not ?

Regards Martin

Martin, the rear of the rails on your 300 will have what appears to be fins. On the 375, they will be milled parrallel to the rest of the rail. In order to dump the cartridge directly into the rear of the box, this modidication will need to be done.



Chuck

Not true Chuck, The cartridge will feed jut fine without messing with the feed rail. All these belted magnum cases are based on the H&H cartridge and will feed like they were on ball bearings without any rail work. Been there, done that!



If you don't own this rifle yet, you can even save your self more time and money by buying a M-70 that's chambered for a .300RUM or a 7mmSTW and simply re-barrel it and you're finished.



Terry

TC1, I have said absolutely jack squat about feeding.

Chuck

OK Chuck, I'll say it. It will feed, extract, load, unload and shoot without all the extra work you're talking about doing to it! period!



I've had this done and I know it will work just as the Winchester tech guy does.

I'll be more than happy to post some pics if it'll help.



Terry

In case I wasn't clear enough the first time: Winchester model 70 Classic actions that house the 30-06 family of cartridges as well as the belted short magnums utilize a shorter, or blocked long box than the long belted magnums. At the rear of the feed rails on these actions, behind the block in the box the rails tail inward. When the block is removed in an existing box or a longer box is installed, these "tails" prevent a cartridge from being dumped directly into the back of the box. Instead, the cartridge must be slid rearward under the tail. This same tail also prevents the rear of the cartridge from resting in the proper place and holds it down in the box farther than it needs to be. Feeding these cartridges into the box correctly, and ultimately having them eject properly, is also why the rear bridge should be milled rearward.

You do what you want, but an incureable desire to pay a gunsmith as much money as I can is not why I have it done.

Chuck

I posted the same time you did and in response to this statement:

Quote:

---

OK Chuck, I'll say it. It will feed, extract, load, unload and shoot without all the extra work you're talking about doing to it! period!

---

Bull Shit, I've done it both ways. Have you?



Chuck

Chuck, I've done it the way I said I've done it and it works flawlessly and why wouldn't it?. You need to settle down boy and maybe grow up a little, No need to start cussing over a .300H&H.



I would continue this with you, but you've obviously gotten emotional about it. The guy that ask the question can do whatever he wants and so can you.



Terry

Well, I agree with Allen's statment about different ways to achieve the end product. I have done exactly what the original poster is wanting to do. My rifle does everything a rifle is supposed to do and does it flawlessly. Sure I could have spent more $$$ on it but I didn't feel the need to. like I said in an earlier post, the rifle loads, unloads, feeds and shoots flawlessly. that was the goal and it was achieved.



Maybe I could have been a little more diplimatic with Chuck. Oh well, I'll try to do better in the future.



Here is a picture of the rifle. It started out as a 7mmMag and has become a .300H&H I shipped the stock yesterday to be checkered. When I get the stock back I'm calling it finished. This project has been a lot of fun mainly because it was taken at a very leisurely pace.







Terry

One thing I can tell anyone about Chuck is that he does everything from the standpoint of how WELL he can things done, not how cheap. In that regard, as well as many others, he and I have a lot in common, and I respect him greatly. Based upon the design and quality of work that Bill Leeper has done for Chuck in the past, there's no question that if I were a Canadian rifleman, he's the man I'd hire to build my hunting guns.



There's also no question that there are any number of ways to skin a cat, and a project like a conversion to .300 H&H can indeed be done with replacement Winchester parts, magazine modifications to the existing magazine box, etc. That's the way to go if you want to minimize your investment and still come up with a workable rifle.



Is this as good a way to go as anything else? NO! Cost aside, the best proceedure is to throw the Winchester magazine box and follower away and invest in a properly dimensioned box and follower system from Ted Blackburn. These boxes are much thicker and of much higher quality than the flimsy Winchester boxes, plus the hold four-down and feed flawlessly if they've been installed properly.



I would also have the receiver blueprinted and remachined and have the loading port opened up for easier and more reliable loading, as well as surer ejection. Even Winchester opens the loading port on all long belted magnums from 7mm STW thru .458 Lott, and it was also standard factory proceedure for the limited number of Classic version .300 H&H and .300 Weatherby rifles they've built. Is opening the loading port properly important? Yes!



While I was at it, I'd also replaced the factory extractor with a machined, spring-steel unit from Jim Wisner, plus I'd toss the factory bottom metal away and get a new replacment set from Ted Blackburn.



I'm like Chuck: I don't care about how cheaply I can get a job done, and I care about how well I can get it done.....



AD

I can't help care about common sense. It seems that the rifle is a 300 WM now that shoots. One would have to change the barrel and modify the action to use a cartridge which will shoot the same bullets!

This is not common sense. Nor is spending the most money for instance.

Thanks

Terry,

That's a very pretty rifle. Wood trumps plastic. Thats a rule.

Well boys it seems I will have to compromise on this one a bit.
Just for clarification :
I don't have the rifle yet,just ordered it Friday.
It's a L.H. M70 LT in 300WM (not short).
The choice in LH rifles is limited to the shorts and the 270,30.06,7 Rem M and the 300WM.
The sole reason for doing this is to end up with a set of H&H, CFR, LH, Winchesters.
I never had much use for the 30cal's other then the 308 because the 33's do things so much better.

I am not a man of unlimited sources and I would like to do this right without spending more than I have to ( have a M1999 action to deal with after)
Looking at the feedback I need/like to:

1) rebarrel because setting the barrelback will leave a gap
in the barrel chanel.
2) blue print the action (like it to shoot straight)
3) modify the mag box or buy new parts (may be able to cut
some corners here
4) mill the receiver rings ?? the pre 64 300H&H had it done,
Chuck had it done TC1 did not and seems to work OK.
I think Bill Leeeper will have to be the judge on that
one.
5) open sights or 1/4 rib ?

My oh my what am I getting myself into,well lets see the gun first, then see how it shoots ,then talk to Bill,work some overtime and take it from there.

Dam nice looking rifle TC1.

Thanks Martin

Well Martin, If you want a matching set of H&H's, you really don't care much for .308's and you're already committed to financial ruin . How about the one on the right, It's a .338/.300 H&H, you can have your cake and eat it too .



Terry