Thanks for responding, Cecil. When I started this build, from 03A3 to 03A4 I went and looked at a friend's real 03A4. I noticed the bolt root cutout on his A4 - and none on my ordinary 03A3 reciever. After messing around with two replica bolts I bit the bullet and bought a Real A4 Bolt (Wow, $$$). Installing it in the A3 action, I noticed that, unlike every other M1903 Springfield I have ever handled, the bolt appears to stop, just short of closing. I assumed it was the bolt handle cutout in the stock until I took the barreled action out of the stock - nope, still would not turn all the way down and locked like any regular non-scoped 1903.
So, looking at the right side of your real A4 action, look at the bolt's safety lug directly in front of the reciever bridge. Is it resting on the right reciever rail - or not? I was told firmly here that the A4 Bolt was all you needed to convert an A3 to an A4 - and I'm sure it will fire - but shouldn't the bolt be turned all the way down, safety lug touching the rail? I can see that mine will not do so without machining the reciever - because it is putting a shiny line on the underside of my bolt's root. I just want to know for sure how a real A4 looks before I go to a machinist. CC
Colt, Glock and Remington factory trained LE Armorer
LE Trained Firearms Instructor
Col. Colt With the bolt handle in the down position, the safety lug is resting on the receiver rail...regards
Thanks so very much, Blackhawk. I need to see if I can borrow a real one and get accurate milling dimensions. I don't want to fire it without the locking lugs where they should be. CC
Colt, Glock and Remington factory trained LE Armorer
LE Trained Firearms Instructor
I've tried to fit several "real" A4 bolts into varying s/n range A3's, both Remington and SC over the years, for S&G's, and no, they are NOT a universal fit into all A3's.
In the rifles I've owned and handled, the bolt safety lug does, indeed, rest on the rail when the bolt is closed. While I suspect that headspace would be just fine if there is a small gap between the rail and the safety lug, it would be seriously wrong to make a blanket statement saying so. In all cases where there is a question regarding such a thing, it's best to obtain a set of headspace gauges, and check 'er out!
If the headspace is okay, the next thing to check is that the firing pin protrudes far enough to give consistent ignition. I say that because if you take a look at the camming surface in the bolt, and the lug on the striker rod, it really needs to be fully in the bottom of the cut for consistent firing pin protrusion. If the bolt won't close all the way, the cam on the striker rod will hit the camming surface in the bolt and keep it from going fully forward.
BTW, I too, thought that shooting prone, over the bags, would be THE match for this old, fat man......but when the rifle recoiled, I looked like a rocking horse, and lost time trying to get back into firing position.............
Thanks for the confirmation, Darreld. I've been doing this a long time (although not as long with 03's) and I was hoping I hadn't completely lost it! I thought about the effect on the firing mechanism, too, but it looks pretty close and that might or might not be a factor - depending on tolerance stackup, of course.
The more time I spend with these fine old rifles, the more respect I have for the men who used to master them - and use them to such good effect on our enemies. Using a rifle well is a total integration task - Mind, Body, Spirit. I fear that the necessary Concentration has been largely lost, of late, for our more current generations. When you think about how "tuned in" a soldier had to be to his weapon and the environment in the middle of a battle in order to still score hits it becomes all the more impressive. We have some wonderfully skilled military personnel today, and equally as brave - yet riflery is harder to practice with a carbine!
Again, Thanks, CC
Colt, Glock and Remington factory trained LE Armorer
LE Trained Firearms Instructor
Note: If you have an 03A4 replica using an original A4 Bolt and an unmodified 03A3 reciever, you need to check that the safety lug rests on the right reciever rail. This may also apply to gunsmith manufactured 03A4 bolts, but it definitely is a possibility if you have an original bolt. Or it may not even be a problem for your combination of parts. But I recommend you check.
UPDATE: 03A4gery completed!! After a careful evening with the rifle action in a vise, the stripped original GI 03A4 bolt (beautifully reparked GI color by chuckindenver - Thanks, Chuck!), a Dremel tool and some lipstick (!), my original 03A4 Bolt now closes completely, with the safety lug of the bolt resting on the right reciever rail. Originally, with the original 03A3 reciever and a very light angled cut, the bolt was about .020 short of closing, measuring under the safety lug. Using red lipstick in place of Dychem Blue on the bolt root, it was easy to see where the bolt handle was touching the reciever.
My 4.1 million Remington reciever/GI 03A4 bolt combination required removing material from the reciever directly behind the rear reciever bridge, the width of the bolt handle (plus a little) with a line basically from the top edge of the right side reciever rail, angling downward until you match up with the GI bolt notch cut in the stock. Your mileage may vary - I went very slow, taking off a thousanth or two, starting from the bottom edge of the reciever rail and working upward, until the bolt closed completely. I coated the bolt handle root with the "Hooker Red" lipstick after each attempt, until nothing was "kissed" by the lipstick anymore.
Now I find there is still a very slight interference with the GI 03A4 Scant Stock's 03A4 bolt cutout near the forward edge - maybe .008 from fully closing. Probably swelling over time made it a hair too tight - it's a very rough cut and obviously well used Scant GI 03A4 Stock, with a square magazine cutoff cut and a "boxed SA" and circle P Proof marks. Minor, but I will correct it before I take it to the range.
I did notice a definite difference in the "solidness" and steadiness of the bolt in full lockup - Safety Lug down on the Right Reciever Rail vs. any point short of that. With the bolt being held up off the reciever behind the rear bridge, it seemed that the locking lugs did not address the reciever "squarely" and the bolt "rocked" a bit when you manipulated it back/forth or up down. I think this modification is worth doing, so the bolt locking lugs seat evenly when the rifle is fired. One less thing to "move funny" when the rifle is fired, one less variable for accuracy. I will furnish pictures if/when I feel more motivated - sleepy Labor Day Sunday! CC
Last edited by Col. Colt; 09-01-2013 at 01:18.
Colt, Glock and Remington factory trained LE Armorer
LE Trained Firearms Instructor
Revisit the first two pages of this post and look at the pictures. Or look at the link in jgaynor's post there : http://cmpauction.odcmp.com/search.a...w=&show=closed
These are CMP auction site photos of Many 03A4s they have sold. Pictures don't lie. ALL HAVE the CUT!
Warmly, CC
Colt, Glock and Remington factory trained LE Armorer
LE Trained Firearms Instructor