Home Forums Hunting & Shooting Winchester Collectors Esoteric question for the Guru's

This is a bit long, but I hope of interest here, so please bear with me. This all ends with a question for the Pre ’64 gurus.

Some years ago my best friend had a push feed M70 in .338WM. It had a spacer in the magazine. Being a handloader, he removed the spacer, shortened the bolt stop, and had the chamber throat lengthened a bit. This allowed him greater overall cartridge length and allowed him to seat bullets out a bit for more case capacity. Being a push feed, the spring-loaded plunger ejector in the bolt tossed empties as soon as they cleared the action. The whole concept worked pretty well.

Fast forward a few years and I buy a modern New Haven controlled round feed .300WM. I liked his idea, but rather than cut parts, I bought the magazine box, ejector, and bolt stop for the .300 Weatherby. I wasn’t sure I was willing to lengthen the throat, but one step at a time. In addition, as most here know, the .300WM could probably benefit from a bit longer neck to seat bullets out a bit and also to have a bit more neck tension. So, had things progressed well, I had the idea of lengthening both the throat and the neck area of the chamber. I could then use true magnum length brass to form a long-necked version of the .300WM. I was thinking of calling it the “.300 Texas Longneck”, which I thought was kinda catchy. You could still shoot standard .300WM if you had to.

As I said, one step at a time. What stopped me was that the controlled feed ejection system didn’t work well. Because the empties moved back an additional ¼” or so before the ejector hit them, the right hand part of the receiver bridge hampered clean ejection. It would work “ok” if you ran the bolt really fast, but even then it was sketchy. I wasn’t willing to mill the receiver bridge shorter as with a modern true full-length magnum controlled feed receiver, and I wasn’t even sure I was willing to re-throat and otherwise mess with the chamber. I’m not big on modifications I cannot reverse. So I blew the whole thing off. I can get 180 grain Partitions to a chronoed 3000 easy enough. I stopped there rather than find the limit. I figure if you can’t get it done with a 180 Partition at 3000, you probably need more bore diameter for whatever it is you are trying to do.

Finally, my question. Whenever I see a Pre ’64 in .300 H&H or .375 I notice a notch in the top of the receiver bridge and a small notch in the ring to “open up” the action for the longer cartridges. But the right side of the bridge is not any shorter. It would seem to me this geometry would suffer the same ejection issues I did as described above. Yet, I have never heard anyone complain that Pre ’64 M70s in those two chamberings had any issues at all. What am I missing?

Thanks, Gun Doc

Gun Doc, I have 2 P64 Magnum action that is used for my 7mm Mashburn Super and the other is a rechambered 300 Weatherby that started as a H&H. It feeds and ejects excellent, the 7 Mashburn Super seems to be good so far as well.

I have converted a few of the Classics over to 3.6" boxes in order to do exactly that, load rounds longer and utilize the Mag space. I never had any trouble with how they ejected at slow or fast pace with the shorter bolt stop, but do see where the shorter bridge on the rear would assist getting the case clear of the rifle.

Have all of the parts and pieces been polished and smoothed in order to function smoothly? I know if the ejector doesn't move up and down freely it'll give you headaches.

Your cartridge sounds a lot like a 300 Weatherby, or if using the 300 Win case for it, something like a 300 Mashburn Super. Not sure which direction you are going with it but It sounds pretty cool.

Hope some of the others have better info for you. I believe the slot in the top of the actions is merely a clip slot and serves no purpose for function. The smart folks will correct me if I am wrong.

I had a bull gun in 300 h&h. It's a stripper clip slot from what I've been told.

Per Rule, p. 102, "corresponding to the increased case length of the H&H magnums, the ejecting port had two small cut-outs, one at each end, and the H&H actions were never slotted for clip loading as standard clips did not fit the belted case head".

As per the above posts, the openings in the ejection ports front and rear were to accomodate the longer H&H cases during ejection. I can't remember at the moment if these actions used a different bolt stop for ejection purposes.

As per your project, many early Pre 64's were sent out by Winchester to a 3rd party gunsmith to be rechambered to 300 Weatherby- which is based on the original 300 H&H case. Wonderful cartridge on these actions and works great. I have a 300 H&H AI (which is basically the early version of the Weatherby ) on a pre 64 and it is one of the most accurate rifles I own and puts a 180 out much faster than the 300 WM's I've owned- just can't remember the Chrono specs at the moment. Might be a better avenue to take over a wildcat and brass is generally available just about anywhere for the Weatherby case.

Not sure if the New Haven actions can be modified in the same way. Just not very familiar with the post 64 actions besides my 338 WM Classic stainless, which has turned out to be one of my favorite rifles- now that my son has claimed my 300 H&H AI.

Bob

Thanks Pocono. As per usual, you hit the nail on the head. Here's a pic of the top of an H&H receiver for those of you that do not know what they look like. These are not "clip slots":

375 H&H:


The 300H&H receivers were identical to this as well....

My semi-custom 338wm was also built on an H&H receiver:


I know Ken (NMelkhunter) has a 300H&H pre 64 model 70 that was built on a std. receiver (without the front and rear scallops/cut-outs in the top of the receiver) and he says it works great..... Maybe he can chime in and give some input...

As for the modification gundoc is talking about, I believe Mr. Scotty Beretz's also hits the nail on the head with his suggestions. I also believe it should have a modified ejector, which allows the empty case to travel far enough aft to clear the ejection port. Should work like a champ if everything measures out properly.... JMHO..

Damn I hate when the website, my computer, or whatever “burps” and I had to type all this TWICE!

Thanks to all who have responded and thanks to BSA for posting the pic of the Pre ’64 magnum receiver, as it saved me having to find a picture to post.

We sort of got off on a tangent (which admittedly I started!), about the cartridge I envisioned. When I bought the rifle, had the .300 Weatherby been available in the configuration I wanted, I might have gone that way. But I have never considered the difference in performance between the Weatherby and Win. Mag., while definitely a significant difference, to be terribly important to me. Having said that, it wouldn’t hurt to open up the magazine to give the .300 Win. Mag. a bit more case capacity, especially because I tend to favor longer, heavier bullets. Had the longer magazine worked out, it was a logical extension (to me anyway) to continue on to a cartridge exactly like the .300 Win. Mag., but with a longer neck. This would have eliminated a criticism many have of that cartridge, i.e. the relatively short neck. (This issue usually doesn’t give people any real problems, but it is something I would not have done had I been designing that cartridge.) Further, in a pinch, I would have been able to shoot factory .300 Win. Mag. In such a situation, .300 Win. Mag. might be easier to find than .300 Weatherby. The idea was mostly a curiosity, and I wasn’t sure I was willing to pursue it, but I was willing to at least start down the road by swapping some parts. As it turned out, the sketchy ejection issue stopped me. I’m sure I could have modified the rifle enough to make it work, but I decided not to go forward.

Even so, my experience got me curious about the shape of the receivers of the Pre ’64 rifles for the .300 and .375 H&H cartridges. Why did they have the cuts on top of the receiver, but not have a larger opening on the right hand side, and yet, as far as I know, not have ejection issues?

To answer BSA, beretzs, and maybe some others, I installed the magazine, bolt stop, and ejector for the longer .300 Weatherby. The shorter bolt stop was necessary so the bolt could move back far enough to pick up a new round from the longer magazine, and the shorter ejector was necessary so that you could load rounds all the way to the back of the magazine. As far as I could tell, all the parts moved as freely as the original parts. If you look at how a control feed (not push feed) M70 ejects, the ejector pushes the cartridge such that it pivots (clockwise if you are looking straight down at the top of the receiver) and “spins” the cartridge out from under the Mauser style extractor. Because the case was about ¼” farther back before this pivoting began, the forward edge of the right side of the receiver bridge impeded this “spinning” out of the ejection port. (Interestingly, and a bit ironically, a fully loaded cartridge, having more weight and inertia once it got going, ejected better than an empty. This was interesting, but not particularly useful.)

We have already seen a picture of a Pre ’64 H&H magnum receiver. What would be great is if someone could post a side by side picture of a Classic “long” magnum (like a .300 Weatherby) compared to a “shorter” magnum (like a .300 Win. Mag.) I am pretty sure that with the Classics, the distance from the bolt cut to the front edge of the receiver bridge is shorter on the “long” magnums. I assume Winchester did this for a reason, but they did it differently on the Pre ’64 rifles. Yet, no one seems to have issue with how the Pre ’64 .300 and .375 H&H rifles ejected.

Beretzs, did you shorten both the bolt stop and the ejector on the Classic rifles where you lengthened the magazine? I wonder why I had trouble and you did not? Perhaps I have missed something or perhaps I am too particular.

I may never know the answer until I have a Pre '64 H&H in hand along with some empty cases so I can observe the small differences in finer detail. But perhaps not. Surely I am not the first to ask this question.

Again, thank each of you for your patience. I know this is not a great collector issue, but I find it intriguing in discussing the development of one of the best bolt guns ever.

Best,
Gun Doc

I'm going to float this back up to the top because I believe there are some gurus out there with additional insight.

I am going to ask Beretzs again . . . Did you shorten both the bolt stop and the ejector on the Classic rifles where you lengthened the magazine?

BSA, you have a lot of pictures. Do you happen to have any of Classic rifles "side by side" in standard or "standard magnum" compared to longer H&H or .300 Weatherby magnum? The dimension of interest is the length of the right side of the receiver bridge measured in the same direction as the bore (i.e. front edge of bolt cut to rear edge of ejection port down low where the bridge is next to the stock.) I believe this dimension is shorter on the long magnum Classics, but it seems to not be on Pre '64 rifles.

Thanks again all.
Gun Doc

HI GunDoc, I don't have any dimensions that you are looking for. Sadly I sold all of my classics in favor of the pre 64 model 70. Been narrowing chit down to what I can't live without basically. That leaves me with my very faithful 1956 30-06 fwt and my semi-custom 338WM built on the H& H receiver. I believe Scotty can get you those measurements, as he has the 35Newton (I believe) built off a classic action and numerous pre 64's he can measure. Another guy to hit up is pre64win (Jason). He has so many receivers it would make your head hurt... Good luck with your search buddy and really like your posts..

Regards,
Lawrence

BSA,

Thanks for your post. We would all likely be better off in some ways if we reduced our "inventory" a bit. Unless you hunt some really big critters, a '56 fwt .30-06 and a .338 on a Pre '64 action seems like a great combo to me. If you want something smaller for varmints, it doesn't really "need" to be a M70 the way we prefer our hunting rifles.

I enjoy your posts as well. Was just gifted a '50 .30-06 Standard Rifle. I plan to start with 180 grain, eventually to Partitions. How hot is that load of 180/57 H4350? Is that one of your "go to" loads for the .30-06?

Best,
Gun Doc

Hi gundoc, yes that is indeed a "go to" load of mine with the 180gr. partition. It's exceptionally accurate in the 30-06 rifles I've used it in as well. It is a little on the hot side, so approach with caution. Lately I've been messing around with the 200gr. partitions because of one bull that caught the 180gr. from a 300WSM. The 180 has always been a great killer though. I hear you on the varmint rifle. I've been experimenting with an evil black gun that should work nicely for any varmint....




My friends FINALLY talked me into buying one of these damn things. I liked it so much, I ended up buying 2 in the same week!!!!!!!!!!



I don't know what the hell is going on with me man!!!! .. I had my heart set on that nice pre 64 220 swift supergrade too, but now my gun fund is gone..

I like all kinds of rifles, even those evil black ones.

"I don't know what the hell is going on with me man!!!! laugh.. I had my heart set on that nice pre 64 220 swift supergrade too, but now my gun fund is gone.."
Life is short, write the check!

Ha ha... Yeah, but I have a great wife. I don't know how long she is going to keep loving me, if I keep burning up our money on guns... We'll see what happens on June 3rd. at the gunshow. If that supergrade is there, hmmmm...

Gunshow? What gunshow? Albany? Inquiring minds need to know....

Bob

Sorry, been out of town for a bit. I will try to get some measurements for you in regards to the Classics vs P64 H&H and standards.

With the Classics I did have the ejector shortened and put the shorter bolt stop in them. The ejector was exactly for the reason you mentioned, it sticks out too far to let the rounds seat in the magazine.

Thanks for the plug, BSA!

Speaking of things people have... when did you get into "black" guns??? I like your shooting bench as well. You never cease to amaze me. Indeed, my wife would begin asking questions somewhere before the point you have reached

When I get a chance I will post photos of the latest custom job working its way through our shop - a very "black" pre-64. A carbon fiber barrel and stock, built on a 1959 magnum action. For an old gun, it definitely meets the intent of making a very "tactical" looking pre-64. My dad cringes when he sees it, but it's really starting to grow on me... maybe I will keep this one!

Thanks again!

Justin

Indeed... we're ready to help with your next custom build. We can get you started with pretty much any version of model 70 receiver Winchester ever made.:




A 1963 short (.458) magnum action mated to a Christensen Arms carbon fiber barrel chambered in .300 Win Mag. It all sits in a Brown Precision stock. It is awaiting final bedding of the action into the stock, cerakoting of the receiver, and hydro-dipping of the stock and scope. Without question, beauty is in the eye of the beholder, but if this rifle shoots anything like its price tag says it should, then it's a beauty in my book. The problem with this rifle will be its weight. Including the scope, the finished rifle will weight less than 8 lbs. I don't want to imagine how bad this thing will kick when loaded up with 210 grain bullets!

See, he even stays up late at night... .. Just waiting to help out the next guy that needs old winchester parts...

Thanks Jason. Yeah, I got the bug bad man!!!!!! I just bought a really cool Noveske upper from a guy that worked for Noveske building rifles there. I plan on building a lower for that upper and rock that AR challenge a bit.... .. Thanks for supplying us with those cool Winchester model 70 parts too man. You know my smith is getting out of the business, so we will need guys like you to keep things rolling... Oh, by the way, that is a bad azzed model 70. I hope it shoots at least as good as my brown precision PoundR stocked 338wm.... . Post a pic when you get that one done. Looks like it's going to be damn near perfect, except for that carbon fiber barrel... I might have to agree with your dad on that one...

It might have been you who told me once in reference to CF barrels "Remember, wraps are for sandwiches." LOL. I love it.

When I talked with Christensen Arms about how to vice up the barrel, they told me to treat it like steel. I was scared, but I've cranked that thing down in the barrel vice twice now without leaving a mark - it's about as tough as you could imagine.

In my day job, I am in charge of marketing the 787 for Boeing, so I'm a particular fan of carbon fiber. It seems appropriate that I should hunt with this thing

More pic to come when I finish her.