I'm looking at buying one in 300 Win Mag, and the serial number indicates '72 year of manufacture. Is this definitely a push feed action?

Yes

Look at a picture of a control feed bolt and a push feed and you will know.

None of the pictures show the bolt face. I could tell it wasn't a true controlled feed, but I didn't know when the controlled round push feed hybrid was introduced.

Additional question: Is this floorplate considered a one piece hinged?

Pretty sure it’s push feed only for that year and separate trigger guard and floorplate. The Classic action reintroduction and the “controlled round push feed” both were in the 1990s.

Ok thank you. It's hard to tell from that photo. I'm looking around for a new hardwood stock.

Extremely appropriate avatar.
Wasn't that one of the key differences for post-1964 M70s?

Yes.  You can see the extractor on the side of the bolt of a controlled feed gun.  I would not be put off by a push feed M70 however.  I have a 1965 edition in -06 that is one of the finest shooting rifles I have ever owned.  It will print 5 into .7 inch at 100 meters and do it on demand.

Frankly, benefits of controlled feed are somewhat questionable except perhaps on a dangerous game gun.  Even most contemporary military bolt guns are push feed.

I have a late '60s Model 70 barreled action in 7mm Rem Mag.  A '69 if I recall.  It is custom stocked from a nice piece of walnut, hand checkered.  It is right at 1 MOA with good quality hunting ammo, and just under with match ammo.  I don't think I'm missing anything practical by it not being controlled-round feed.

Thank you. That makes me feel a little better about this purchase.

I have an M70 of every flavor and the push feed is my favorite.  The hybrid works fine but is pointless to me.  The only benefit IMO to the original Mauser style is the amount of rim engagement the extractor had, not the controlled feeding.

I take that back.  There are other benefits.  No extractor pressure on the case.  No need for an additional bolt guide rail that makes push feed Winchesters a PITA to feed from magazines compared to just about anything else, since the extractor worked as a bolt guide.  All of those are more meaningful than controlled round feeding to me.  But I don't do ninja rolls while working the bolt between shots at dangerous rhinobuffalodiles in the outback.  

I like the push feeds.  They're smooth, straight, accurate actions with flat bottoms, real recoil lugs and the best safety on the market and were superior to their primary competitor in every way.

Have  guns with both controlled feed (Husqvarna) and push feed (ARs, Sako, Winchester). Every damn one of them goes bang, every time, and does so with very good accuracy. When someone comes up with a test that can isolate the CF/PF as the only variable between a given pair of rifles, and can prove the superiority if any, of one over the other then the hash will be settled.

I understand OP's desire to determine which one the rifle he is contemplating buying has, but unless you are shooting the much maligned rhinawildebeeelephabuffacroc, it'll never ever matter in the grand scheme of things.

Bear in mind that the Garand, M14, M1 Carbine and AR15/ M16 are all push feed systems.  

I can definitely see the argument for wanting a controlled feed on a bolt action combat or dangerous game rifle but not having it isn't the end of the world

All rifles with dual opposed locking lugs and 90* bolt lift are inferior copies of the original.

Controlled round feed is not the only feature deleted in the rush to make a product cheaper than the competitor.

That said, if you just want an ugly rifle to go bang for the lowest dollar, Remchester it is !

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