03A3 to 03A4rgery - Anybody cut the A4 Bolt Notch in their A3 Reciever??

[Col. Colt]

I am working on assembling all the special parts and figuring out all the correct modifications to make an 03A3 into a "correct" - except for markings, of course - physically (and functionally) exact copy of an 03A4. As an older, heavier guy, this would be a match I could do well at!

One thing I have not heard much about is doing the Bolt Cutout in the side of the 03A3 Reciever to give clearance for the 03A4 modified bolt to close entirely, all the way, as all the originals were done. As I recall off the top of my head, the cutout I measured in a for real 03A4 last week was about .645 wide and on a 45 degree angle, with the back edge rounded to get rid of a sharp corner behind the bolt root, lining up perfectly with an original 03A4 stock.

If anyone has done this - how about sharing your experience? Any observations that might be helpful? CC

[Marine A5 Sniper Rifle]

There was no such cut out in the receiver. A real A4 bolt fits the receiver with no modification to the receiver.

jt

[da gimp]

There was no such cut out in the receiver. A real A4 bolt fits the receiver with no modification to the receiver.

jt

That was what I recalled too jimmy.

[Col. Colt]

The example gun I saw appeared to have it's original arsenal finish over the cut, and I pointed out the cut to the owner - he thought it was standard on all 03A3s, as well. I thought it had to be real, as the rest of the parts looked right, and his bolt would not completely close in my 03A3 uncut reciver. Curious..... CC

[musketshooter]

If you have to cut the receiver for the bolt, your bolt is incorrect.

[m1903rifle]

1903A4 with notched receiver

I have attached a picture of an original ( although sporterized ) A4 that has the notch. It's one of the early ones in the 3.42 Million range. Could it have something to do with the vintage, i.e. ,early or late?

[chuckindenver]

all genuine A4,s have a mill cut under the bolt root.

[Allen Humphrey]

I'm not sure if there are variations, but the one and only A4 I have held in my own hands has a notch under the bolt root.

[Marine A5 Sniper Rifle]

I repeat, any A4 bolt will fit any 03A3 without modification to the receiver. They all have the milled area shown in the pic. No modification is required (except the unique stock cut).

jt

[Johnny P]

[jgaynor]

The following lnk will take the viewer to a series of recent CMP auctions of A4's and A4 receivers. The descriptions have good close up pictures and the entire s/n range of a4's is covered

http://cmpauction.odcmp.com/search.a...w=&show=closed

I agree all authentic A4's recieivers have the relief cut for the bolt handle root.

Regards,
Jim

[Dan in NY]

Here's #34235xx. Has the bolt cut.., as does my 4,99 mil A4.

great link above, Jim...very informative..

[chuckindenver]

A5 is right. notching the action is not needed if your using a real A4 bolt..if your using a sporter bolt? all bets are off

[Col. Colt]

While it may (or may not) be generally true that "most" A4 bolts work in "most" 03 Actions without the cut, my friends A4 bolt (from a REAL A4) would not completely close in my unmodifided A3 action without the bolt root cut, even with a genuine, US GI A4 cut stock installed.

And with Remington, by 1943 only doing "Essential Operations" to the 03 and 03A3 to speed up and cheapen production (no lightning cuts on the rear sight base of a Remington 03, for example) why on earth would they add an additional, unnecessary cut to the reciever that they did NOT have to?? Not only do they do the cut for the bolt root, they had to finish the edge of the reciever with a curved corner. If making the bolt correctly completely solved this problem, how come Remington set up to do this cut on three different runs of rifles? If it wasn't needed, why was it done? CC

[Randy A]

Col.
Good question, but I for one have installed an original A4 bolt in a few A3's and they do clear without the cut (no, I didn't leave them there). So I got out the calipers and discovered (I have quite a selection of bolts) that the A4 bolts have a longer root than any other 1903 series bolt handle (the distance from the body to the corner of the bend). With the exception of one A3 bolt handle type which I strongly suspect is the bolt type used to make A4 bolts. I believe, on my A4 it would clear without the cut I can only speculate that there was the one or two (like the one you ran into) exceptions that mandated the cut.