M40a1 build guide

[chad3]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: hink</div><div class="ubbcode-body">SDwhirlwind made a batch a while back. You may be able to pick one up from the 'For Sale' forum.</div></div>
Those are the ones. Machinists can make you one or you can take off the sling cut down the width of the shank and reinsert. Both work but the first allows you to put swivel back in.

 

[pre64marksman]

Re: M40a1 build guide

Harris on HTG and witchita swivels-
It may have been something I heard here on the hide or somewhere else but I heard some Marines early in Iraqi freedom still using the A1 actually cut the loop off the witchita stud and fitted a harris bipod to that stud. It was maybe a few Marines and not a common thing I belive I heard. I don't know if that little clamp on the harris units would fit the witchita stud but maybe it would. I'm not recomending it as a solution, I would hate to ruin a good swivel like that.

BTW I heard of a return stock being sold for $1100-that's insane!
Unless at least half that money goes to Wounded Warriors or Marine Corp Families or some other affiliated organization, no way should someone pay that for a well beat stock! Returns are cool either way though for the history and "battle scars" but objectively speaking its "good" condition at best, its a helluva lot of money even for a McStocky!

 

[SDWhirlwind]

Re: M40a1 build guide

At the top of the market when demand was at its peak and common sense at its all time low they were bringing as much as $1800 on fleabay!

 

[eodsix]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 2ballcane</div><div class="ubbcode-body">GregV: I worked under the miss-impression that a scope sn was related to the rifle sn. In pursuit of a pure clone this is not "correct." When I thought about this in a historical context, how could anyone get Unertl (and later USO) and Remington to coordinate their productions lines this way. The bottom line is that they didn't, so if you're attempting to be a "purist" in your clone build the rifle sn and scope sn have no relationship. One might consider this to be a "cool" feature, but not authentic. I can't take credit for this revelation, George @ GAP helped me along. </div></div>

I'm inclined to agree with 2ballcane one this. Matching scope serial numbers to weapon serial numbers, unless they were all made in a custom shop from scratch, would be a logistical nightmare. Cool yes but the only time I've seen any correlation of optics SN# matching weapon SN# was on the M21 rifles and the ART SN didn't match the weapon, the mount did. When the weapon was put together, the AR TEL or ART II scope was married to the parent weapon by stamping the last four of the weapon SN# to the scope's mount above the mounting screw. That way when they removed it to use the PVS-2 or PVS-4 for night ops they could put the same day scope back on.

 

[M40_A1]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: EODsix</div><div class="ubbcode-body">I'm inclined to agree with 2ballcane one this. Matching scope serial numbers to weapon serial numbers, unless they were all made in a custom shop from scratch, would be a logistical nightmare.</div></div>

There's no guesswork necessary. I'm surprised no Devildog snipers have cleared this up yet. The Unertl Sniper serial numbers never matched the receiver's serial number, except perhaps by huge coincidence on a rare occasion or two. Back when the Redfield bases were used, they were serialized to match the receiver, but the scope has always had its own serial number sequence from Mr. Unertl's shop.

 

[grunt0311]

Re: M40a1 build guide

Trying to match SN's to everything is a nightmare and things usually didnt last long. In Vietnam on the M40 they would serialize the scope and the scope mount. The Redfield scopes never had their own SN and the SN that they had was that of the gun. Things would rarely stay together as scopes and rifles would go bad and they would mix match them.

Now the Unertl's were never serialized to the gun. They carried their own SN and the same goes today with the S&B.

 

[pre64marksman]

Re: M40a1 build guide

Is there a new type of gun finish that replicates the look black oxide? Anyone builders that still do black oxide or is it pretty much avoided for health reasons?

 

[kft101]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pre64WINmarksman</div><div class="ubbcode-body">Is there a new type of gun finish that replicates the look black oxide? Anyone builders that still do black oxide or is it pretty much avoided for health reasons? </div></div>

I think Connor at Celtic Rifles will still do black oxide if you really want it.

 

[M40_A1]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kft101</div><div class="ubbcode-body">I think Connor at Celtic Rifles will still do black oxide if you really want it. </div></div>

For a proper M40A1 build, who <span style="font-style: italic">wouldn't</span> want it!?

 

[cttbax]

Re: M40a1 build guide

Parkerized black oxide?? I think that is the rem finish... I could be wrong?

 

[M40_A1]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cttbax</div><div class="ubbcode-body">Parkerized black oxide??</div></div>

Parkerizing is a phosphate finish, while black oxide is akin to bluing. The two are not the same thing. Stainless (as in a M40A1 barrel) cannot be Parkerized, but there are stainless bluing salts, and that was the process used on the M40A1s according to the sources I have read and heard. Has The Corps switched to a powder coat or something similar? I'd like to know.

The Remingtons are most likely just heavily sand or shot blasted and blued.

 

[chad3]

Re: M40a1 build guide

Black oxide does not stick to the barrel and rubs off pretty easily. I had an old picture of an M40-a1 with a shiny barrel it was worn so bad. Celtic Rifles is the only one that I've seen that does it (ie mine is from him).

 

[Emilio]

Re: M40a1 build guide

This one?

 

[M40_A1]

Re: M40a1 build guide

When I did my build in 1990, I bought the SS salts from Brownells' and gave them to my gunsmith. He did a fine job on it and it still looks great. The trick is in the metal preparation- blasting and etching.

 

[grunt0311]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: chad3</div><div class="ubbcode-body">Black oxide does not stick to the barrel and rubs off pretty easily. I had an old picture of an M40-a1 with a shiny barrel it was worn so bad. Celtic Rifles is the only one that I've seen that does it (ie mine is from him). </div></div>

How much did it cost to do the black oxide? Im having an M40a1 built while im on deployment and wanted this process done as well.

 

[M40_A1]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Emilio</div><div class="ubbcode-body">This one?

</div></div>

There's more to that one than black oxide worn off the barrel. The scope, rings, receiver and barrel are all white. I suspect may have been due to oils and/or glare, or most likely just bad photo enhancement.

 

[jasonahull]

Re: M40a1 build guide

If anyone is interested, i found a complete 243 on gunbroker.
The serial number is six digit and the first 3 numbers are 327.
It is an adl rifle. Auction # 263073325

 

[sab9259]

Re: M40a1 build guide

I recently bought a 700 that was worked on by a local smith that has a D.D. Ross one piece base that resembles the M40 base. I think Ross has a gov't contract now but were they ever used on a M40 in any configuration?

FWIW- Im not real interested in a M40ish clone right now and was just seeing what I've got on my barreled action and if there was any added value. Thanks

 

[kft101]

Re: M40a1 build guide

Unertl Mount Question:

Anybody know the thread pattern for the ring screws used on the actual Unertl M40A1 mounts? Or where I can find some for sale?

I have a real Unertl mount and would like to get some spare screws for the rings.

I also have the USO repro mounts and Redfield bottom screw rings and they all use differently threaded ring screws. The Redfields are shorter, fatter and have finer threads. The USO and Unertl screws are similar, but USO's are a bit finer in threading.

Thanks guys.

 

[M40_A1]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kft101</div><div class="ubbcode-body">Unertl Mount Question:

Anybody know the thread pattern for the ring screws used on the actual Unertl M40A1 mounts? Or where I can find some for sale?

I have a real Unertl mount and would like to get some spare screws for the rings.

I also have the USO repro mounts and Redfield bottom screw rings and they all use differently threaded ring screws. The Redfields are shorter, fatter and have finer threads. The USO and Unertl screws are similar, but USO's are a bit finer in threading.

Thanks guys. </div></div>

I have an original Unertl and Redfield mounts (sorry, no USO to compare). I took some measurements and came up with these:

Unertl ring bolts-
Allen key: 7/64"
Head diameter: .222"
Shank diameter: .135-.136"
threads per inch: 32
thread size: 5/32-32 according to my chart based on the dimensions
____________________
Holes in Unertl bottom rings-
Diameter for bolt head: .232"
Diameter for bolt shank: .141"

-------------------------------------

Redfield ring bolts-
Allen key: 7/64"
Head diameter: .236-.238"
Shank diameter: .161"
threads per inch: 40
thread size: 3/16-40???- not on my chart, but based on the dimensions
____________________
Holes in Redfield bottom rings-
Diameter for bolt head: .253"
Diameter for bolt shank: .167"

 

[eodcam]

Re: M40a1 build guide

when the accu-range was being used on the A1, did they use the existing mounts and rings from the M40. Anyone have and leads on an A1 Lugged replica mount?

 

[SDWhirlwind]

Re: M40a1 build guide

No they used a Redfield 700 marked base with the square corners, not rounded corners on base like current models. The square cornered bases were only made a couple of yrs before they started rounding them off at first a little then moreso later on. Rings were the medium bottom screw Redfields. No lugged mount until Unertls were used with their base.

 

[kft101]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 10Xview</div><div class="ubbcode-body">

I have an original Unertl and Redfield mounts (sorry, no USO to compare). I took some measurements and came up with these:
...

</div></div>

Thanks, 10Xview.

Contacted all three manufacturers for the specs straight from the horse's mouth.

Redfield states the ring screws are 6-40.

Still waiting on the other responses. Will order the screws from Brownells, verify, and update this thread with the info when I get 'em for others' knowledge.

 

[Shoot 1st]

Re: M40a1 build guide

I like it in its stock form.

 

[eodcam]

Re: M40a1 build guide

Awesome SD, I appreciate it!

 

[SDWhirlwind]

Re: M40a1 build guide

Guess I should have made my comment clearer concerning the corners. The rear corners are perfectly square and not rounded but front is rounded a bit. The M40 used a 40X marked Redfield base but had square corners front and rear of base. Later 70's and into the 80's it seemed every several yrs they rounded front and back corners a bit more. Thought there was a pic around the start of this thread that showed pics of the correct bases??? I didn't go back and look now though.

 

[eodcam]

Re: M40a1 build guide

Thanks SD, I think I have a few of those mounts. I believe the VS I just bought has a mount like that on it. I just need the bottom screw medium rings. I have a crap ton of the 4 screw top mounts. I have a badger repro for the M40 build but now that I'm thinking an A1 would be nice too, I want to start collecting parts for that build. Speaking of the A1 if I use a Weaver T-10 what would be the correct mount for that?

 

[SDWhirlwind]

Re: M40a1 build guide

There were only 2 mounts used on the A1 setup that I know of, the 1 I mentioned and the Unertl/USO setup. So if you use a T-10 then the first was used. Unertl base used for Unertl scope I assume 100% of the time after introduction and adoption of that optic.

I thought there were pics at the start of this thread showing the Refield base but couldn't find them last night. However there have been a bunch of pics deleted since its start. I don't know where to look for a pre Unertl pic????

 

[eodcam]

Re: M40a1 build guide

No worries, I appreciate the knowledge. I know it's been mentioned before but What's the best source for the Bottom metal for an A1 build? I tried contacting Williams but not sure If I hit up the correct company. They never got back to me, I guess they split? I'm getting tired of getting outbid on ebay! Thanks Again!

 

[kft101]

Re: M40a1 build guide

Dennis, it seems the ring/base combo for the mounts were mixed and matched a bit when transitioning from the M40 to the A1.

Below are some pics taken from auction sites of two early M40/M40A1 in-betweens. The one with the Unertl scope looks to use the old Redfield base and 4-top-screw rings, while the one with the green-anodized Redfield scope also uses the Redfield base, but looks to have tall bottom-screw Redfield rings.

Both sport the early McMillan smear stocks, but oddly, the one with the Redfield scope has the old aluminum butt-plate.

Pics:

 

[SDWhirlwind]

Re: M40a1 build guide

kft...Think you are right. Kinda a Heinz 57 parts lot the 2112's have stashed. The old Redfield I am sure are high rings. As far as the Unertl pic with base I thought I seen somewhere the complete square corners in rear like the M40 40-X marked base? I have I think 4 different 1pc Redfield bases from late 60's on into the 80's and each look a bit different as far as front and rear corners. Later ones are really rounded off.

I am sure they bought different lots/years to replace parts as time went by and chit was lost, damaged etc. Probably some long necked skinny dude didn't/couldn't get a good sight pic so the tall mounts were used. Adapt the equipment to the shooter and not other way around if it works!!!!

Thanks for posting the pics and hope all is well in NY? Well, as good as it can get

lol

 

[furburner]

Re: M40a1 build guide

Will a Timney work in m40a1 can it be modified to fit??

 

[M40_A1]

Re: M40a1 build guide

From what I understand from "Death From Afar", the square cornered "40X" bases were the originals, and used on the M40s and into the M40A1s. The rounded cornered "SA700" bases were used as replacements in the late 1970s, so I would imagine they could also be found on the sticks from time to time, until they were all phased out by the Unertl unitized bases in the early 1980s.

On my build I used the SA700 base with the rings spot welded thereon as was done later on to stabilize the setup. The dovetail sits a bit forward of center between the front base screws, and I had to mill a rounded groove in the front of the front ring base in order to completely access the front base screw.

 

[RMPSTRAT]

Re: M40a1 build guide

to make matters worse there are also different lengths to the Redfield bases

 

[M40_A1]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kft101</div><div class="ubbcode-body">

Redfield states the ring screws are 6-40.
</div></div>

That's interesting, because the MAXIMUM major diameter (Class 3A) for a 6-40 is .1380", while the bolts in mine measure .161" which is closer to a #8 size. I wonder if the size changed somewhere along the way. For whatever reason, the gun industry is notorious for using very odd thread sizes.

For example, the Wichita sling swivel stud's thread size is 7/32"-40 (or at least it was in the 1990s), and requires a #9 drill for the pilot. Try finding that thread size in the shop books! I don't know how I found the tap for it in 1990, but I did.

 

[kft101]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 10Xview</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kft101</div><div class="ubbcode-body">

Redfield states the ring screws are 6-40.
</div></div>

That's interesting, because the MAXIMUM major diameter (Class 3A) for a 6-40 is .1380", while the bolts in mine measure .161" which is closer to a #8 size. I wonder if the size changed somewhere along the way. For whatever reason, the gun industry is notorious for using very odd thread sizes.

For example, the Wichita sling swivel stud's thread size is 7/32"-40 (or at least it was in the 1990s), and requires a #9 drill for the pilot. Try finding that thread size in the shop books! I don't know how I found the tap for it in 1990, but I did. </div></div>

I think you're right.

From US Optics, their repro mounts use 6-40 ring bolts, and from a reliable source, the Unertl mounts use 6-32 ring bolts. Comparing a bolt from each mount side by side, that sounds right, as they're both the same diameter but the Unertl has a more coarse (lower) thread count.

Comparing them to a bolt from an original Redfield bottom screw ring, I think I got bum scoop from the Redfield guy. Maybe he was thinking about their newer rings, but the bolts used on the bottom screw rings are definitely not 6-40. Just eyeballing the bolt side by side with the others, I'm guessing it's 8-40.

UPDATE: OK, confirmed that the Redfield bottom-screw rings use 8-40 thread pattern bolts. Swapped the bolts from a set of Badger rings (and they use 8-40) and they fit perfectly between the Badger and Redfield rings.

 

[RMPSTRAT]

Re: M40a1 build guide

the four screw rings are 5-44 if I remember right

 

[Joe Stansbury]

Re: M40a1 build guide

Just picked up a 6 digit action today. Now the next thing on my list is the barrel.

 

[eodcam]

Re: M40a1 build guide

Another Question, Did the Early A1's use the same barrel as the original M40 or was the Barrel change done when they restocked them? I guess I'm asking if there were any fiberglass stocked M40's? Thanks!

 

[eodcam]

Re: M40a1 build guide

Here's a pic of my Mount Collection, one day I'll have an Unertl/USO mount to add to it So true about Redfield mounts being different.

 

[eodcam]

Re: M40a1 build guide

Potential 6 digit Builds!

 

[Jerry W Hudson II]

Re: M40a1 build guide

Well got an "E" prefix Remmy action made in 1998 sent it GAP for a M40A1 spec build. Bought a US Optics scope base yesterday. I'm on the list for the latest MST-100 run. Maybe in 6 months or so I will be able to post some pics.

 

[eodcam]

Re: M40a1 build guide

Awesome JWHII! By the way, where did you get the USO Base?

 

[Jerry W Hudson II]

Re: M40a1 build guide

Here on the hide from kft101

 

[irishshooter]

Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JWHII</div><div class="ubbcode-body">Well got an "E" prefix Remmy action made in 1998 sent it GAP for a M40A1 spec build. Bought a US Optics scope base yesterday. I'm on the list for the latest MST-100 run. Maybe in 6 months or so I will be able to post some pics. </div></div>

theres another run? I thought it was just a rumour? How do you get on the list?

 

[Jerry W Hudson II]

Re: M40a1 build guide

They had some cancellations there were 2-3 openings left per Becky a week ago

 

[BasraBoy]

Re: M40a1 build guide

Not sure on the rules on posting links to auctions...so mods, please delete if this is a breach.

Just saw this on "that" auction site:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200623537306

Not cheap but for that 100% spec M40 build...great opportunity!

I got my USMC marked x8 Unertl from this guy and he is 100% genuine (at least as far as my experience with that scope was concerned).

 

[Jerry W Hudson II]

Re: M40a1 build guide

There are some USMC M40A1 return stocks on gunbroker and a non spec M40A1 clone rifle.

 

[eodcam]

Re: M40a1 build guide

Couple of returns in here, the woodland is gorgeous and it was hidden under paint. Can't wait to check out the Smear!

 

[Jerry W Hudson II]

Re: M40a1 build guide

"F-N" NICE!