M40a1 build guide

#554
Re: M40a1 build guide

I have been reading off and throught this thread. It is killing me. I am selling everything I can to make a M40A1esque rifle. I am also wanting to help out an ex USMC SS build a rifle the will be given to him.

I love this thread.
 
#555
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Ben777</div><div class="ubbcode-body">I have been reading off and throught this thread. It is killing me. I am selling everything I can to make a M40A1esque rifle. I am also wanting to help out an ex USMC SS build a rifle the will be given to him.

I love this thread.
</div></div>

Heros all of them!
God bless our Troops!
 
#558
Re: M40a1 build guide

In regards to the early M40a1's, the crown on the barrels can almost be a mish mash of slightly different angles, depths, etc., especially over time. There was really no absolute blueprint or "bible", if you will, but had a list of requirements & basic instructions for each build or re-build. The very minute details all depended on which armorer did the work and when, which could really change it's personality when these rifles came into the depot for rebarrelling or repairs. The knowledge was passed down from armorer to armorer which some may have had different machine shop backgrounds, knowledge, and skill. This can and did change the personality of each rifle to a certain degree. Much like the telephone game, techniques change slightly over time and through generations.

I've seen a lot of these bedding jobs and most weren't things of beauty compared to some of our resident gunsmiths here but they obviously worked. As with the McMillan stocks, each M40a1 was different in it's own way. This is also true about the serial number stampings. I've seen the last 4 digits on some of the bottom metal and bolts that are unlike most of the pics here. Some bolt numbers sit further down on the flat of the bolt or have the numbers run vertically up & down the bolt. The bottom metal number placement can be even more unique and all over the inside of the floorplate. Sometimes the stampings were X-ed out with an electric pencil or stamped during parts replacement. The stamps could be heavy on one edge & light on the other and the numbers weren't perfectly straight or spaced evenly as some may have noticed on their return stock's bottom metal. As long as they were legible and in the proscibed area it was good to go. Some of these earlier builds didn't have the taper on the recoil lugs either. Think of the Garand cut op-rods, or M1 Carbine flat bolts & sights. Not all rifles were completely updated with the later build techniques or parts. There were no textbook cookie-cutter M40a1's. These were tools that had to function reliably and accurately per the USMC's set minimum standards. They weren't built to be works of art or fly to the moon, they just had to work.

It wasn't until the M40a3 & M40a5 that the USMC wanted to create a set of standards on builds to include having an actual blueprint made up of the stock inlet which have special bedding pockets built in. An engineer had even come down to McMillan's shop to check & compare the A4 stock inlets to the blueprint. Times had changed, and now they are even looking at future chassis systems.

These M40a1 clone/replica builds remind me of classic car restorations. You can have a nice driver with updated drivetrain or one that has period accessories. Some are detailed enough to have a complete concourse restoration with the correct nuts, bolts, decals, and have the assembly line grease pencil markings replicated in the correct locations. This, of course, ends up costing large amounts of money and time. It is a labor of love though and most know that they will not experience huge profits, especially when they add the time it takes to gather all the right parts. But it is theirs and they want their car exactly as they envision it to be. However, all are great for the fact that they can still be enjoyed, some to be driven or even raced, while others sit in a climate controlled museum to be appreciated as an example of the period. To each, their own.
 
#559
Re: M40a1 build guide

Konabully is absolutely correct. Each M40A1 was/is as different as each McMillan stock.

Here are a few pictures of one that I had in the armory at PMO Camp Pendleton. We had four and none of them were the same.

Three had very early stocks and one had the later "woodland" camo pattern. One was a C671XXXX serial. Two were only two serial numbers apart, 221532 and 221534, one of which actually had "Property" inscribed with an electric pencil between the "U.S." and the serial number. Tell me you've seen that characteristic mentioned in one of the books that get cited here on a weekly basis!

Anyway, in the pictures (sorry for poor quality, taken out on the range one day) you can see how this particular weapon's bolt handle was marked. Also notice the polished blue, long bolt plug/shroud. It was a later production bolt with the guide rail slot in the right-hand lug.

In the picture capturing the "RTE-P" stamp, if you look closely at the leading edge of the action you'll notice that the edge is distorted. This is where at some point in the past, this rifle's recoil lug was welded onto the action. It had since been removed, leaving behind the jagged edge.

Also see the correct shape of the "thumb clearance" cut of the clip slot. Notice that the "U.S." stamp is high and close to the scope mount. Standard screws in the scope mount, not Allen or Torx. Picture of the muzzle shows the general characteristics.

Somewhere I've got a picture of all four rifles together. I'll see if I can dig it up.

photos138.jpg

photos139.jpg

photos140.jpg

photos141.jpg

photos142.jpg

photos143.jpg

photos144.jpg

photos145.jpg

photos146.jpg
 
#566
Re: M40a1 build guide

I dont think that all A1's are now A3's. I do remember seeing pictures from 2009 of PMO in Pendleton that were still using the A1's. I know that I do have some of those pics and Ill post them as soon as I can find them. If there are any A1s in service Im sure that PMO are using them.
 
#567
Re: M40a1 build guide

Correct. PMO's, or PMO Pendleton anyhow, will be using the M40A1's for quite a while. PMO rifles see far less use than rifles that are out in the Fleet. Because of this, their service life is much longer and the Marine Corps is not going to scrap a serviceable weapon just because there's a new version out there.

In '05 we turned-in one of our rifles because it was due for a re-barrel. We got a brand new rifle back in return; it had 49 rounds in the gun book.

Having said that, I think PMO Lejeune was using M16A4/Acog's as their M/O rifles by '05.

Grunt,
I know the pics you're referring to. They were from either Stumps or Barsto.
 
#568
Re: M40a1 build guide

Skunk,

I want to thank you. It's not often you find actual pictures of the old A1 that aren't in a grainy black and white leaving you to try and figure out what the hell you're looking at. That just made me get mine out of the safe just to compare. Thanks again!

jeff
 
#570
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Skunk</div><div class="ubbcode-body">Konabully is absolutely correct. Each M40A1 was/is as different as each McMillan stock.

Here are a few pictures of one that I had in the armory at PMO Camp Pendleton. We had four and none of them were the same.

Three had very early stocks and one had the later "woodland" camo pattern. One was a C671XXXX serial. Two were only two serial numbers apart, 221532 and 221534, one of which actually had "Property" inscribed with an electric pencil between the "U.S." and the serial number. Tell me you've seen that characteristic mentioned in one of the books that get cited here on a weekly basis!

Anyway, in the pictures (sorry for poor quality, taken out on the range one day) you can see how this particular weapon's bolt handle was marked. Also notice the polished blue, long bolt plug/shroud. It was a later production bolt with the guide rail slot in the right-hand lug.

In the picture capturing the "RTE-P" stamp, if you look closely at the leading edge of the action you'll notice that the edge is distorted. This is where at some point in the past, this rifle's recoil lug was welded onto the action. It had since been removed, leaving behind the jagged edge.

Also see the correct shape of the "thumb clearance" cut of the clip slot. Notice that the "U.S." stamp is high and close to the scope mount. Standard screws in the scope mount, not Allen or Torx. Picture of the muzzle shows the general characteristics.

Somewhere I've got a picture of all four rifles together. I'll see if I can dig it up.</div></div>

Steve, I'd be interested in all the photos; would you please e-mail them to me directly?
 
#574
#576
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pat M</div><div class="ubbcode-body">but $8,500 ouch! </div></div>

Yea, nothing like a 4+ G mark up huh???? Must be the extra stock???
smile.gif
 
#577
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SDWhirlwind</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pat M</div><div class="ubbcode-body">but $8,500 ouch! </div></div>

Yea, nothing like a 4+ G mark up huh???? Must be the extra stock???
smile.gif
</div></div>

Hey, Dennis. How's it going?

I don't think the markup is *that* much. Figuring the current going rate for a return stock, USO MST-100 and base/ring set, Schneider barrel plus proper build costs...why it's <span style="font-style: italic">only</span> 2-2.5k more than the spec build I'm working on!
wink.gif


By the way, Dennis, you have any more replacement studs for these stocks? The couple I got from you earlier are working great and I could use another pair if you have them available.

Ken
 
#578
Re: M40a1 build guide

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

Hey, Dennis. How's it going?

I don't think the markup is *that* much. Figuring the current going rate for a return stock, USO MST-100 and base/ring set, Schneider barrel plus proper build costs...why it's <span style="font-style: italic">only</span> 2-2.5k more than the spec build I'm working on!
wink.gif

<span style="font-weight: bold"> Action $400
Schneider tube $300
Return Stock Current Prices Roughly $1000
New M40A1 stock $500ish
USO mount $400
MST-100 $2750ish
Labor-Thread/chamber, bed, park or whatever $1000

Yea, I didn't figure the return stock in so you are right with the $2-2.5K
wink.gif
</span>

By the way, Dennis, you have any more replacement studs for these stocks? The couple I got from you earlier are working great and I could use another pair if you have them available.
<span style="font-weight: bold"> Funny you should ask, LOL, I kinda forgot about them but I do have 2 more of them laying around, $55 shipped if you want them. Let me know Ken. Suppose offering to trade them for an MST-100 would be out of line
wink.gif
</span>

Ken </div></div>
 
#579
Re: M40a1 build guide

I think we all have to remember that without Mcmillan offering take off stocks for $200 + shipping with bottom metal these spec builds wouldn't have happened.

Now in fairness this seems a little high, but think of what they would have made if they sold those stocks for the going rate of $1,000.
 
#580
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pat M</div><div class="ubbcode-body">but $8,500 ouch! </div></div>

No, $8541.00. Think they will ever sell a M40A5 for $0317.00?
 
#581
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Tim8654</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pat M</div><div class="ubbcode-body">but $8,500 ouch! </div></div>

No, $8541.00. Think they will ever sell a M40A5 for $0317.00? </div></div>

You know I was thinking that yesterday when I saw it. They should sell M40a5 for $0317.00
 
#582
Re: M40a1 build guide

I finnaly got around to shooting my spec build, M40A1 at long range and it is very nice.
It is a smear pattern, return stock, Schneider barrel, TBA MST 100, 6 digit etc.
Shoots as well as the heavy crosshair will let you hold. I shot some 400 yard, 5 shot groups that were averaging 1.5" and very well at longer range as well. Out to 800, which is about as far as I shoot at my house. I like the scope and will be varifying the settings soon, but it is very close with a 175 SMK and IMR 4064. What a pleasent rifle.
 
#583
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rth1800</div><div class="ubbcode-body">I finnaly got around to shooting my spec build, M40A1 at long range and it is very nice.
It is a smear pattern, return stock, Schneider barrel, TBA MST 100, 6 digit etc.
Shoots as well as the heavy crosshair will let you hold. I shot some 400 yard, 5 shot groups that were averaging 1.5" and very well at longer range as well. Out to 800, which is about as far as I shoot at my house. I like the scope and will be varifying the settings soon, but it is very close with a 175 SMK and IMR 4064. What a pleasent rifle. </div></div>

It didn't happen unless you post pics.
laugh.gif

Put up specs on a build like that and you know pics are required. Haha.
 
#588
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: chad3</div><div class="ubbcode-body">Carter,
You are kicked out of this thread...
Chad </div></div>

After you check his credentials, you'll invite him back in....
grin.gif
 
#589
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JRose</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: chad3</div><div class="ubbcode-body">Carter,
You are kicked out of this thread...
Chad </div></div>

After you check his credentials, you'll invite him back in....
grin.gif
</div></div>

Well that brings up several questions then so does this person know what they're talking about? Many of us are sporting spec clones built by an ex armorer and they are serialized on all components.

What's the story?
 
#590
Re: M40a1 build guide

That's the same thing I was saying. 99% of people around here would say that this was completely incorrect.
Which would lead me to say, Carter come on back and let us know...
JRose, I know what he has built, but why would all say stamp and he doesn't?
Chad
 
#591
Re: M40a1 build guide

I have done some more range test with the full spec clone and MST 100. Barrel is 24" from front of lug to end. TBA rifle, Schenider barrel. USO USMC mount.
I have found that the following load will shoot exactly on the settings to 800 yards.
This is a top end load and should be worked up to, I am calling it Max in my rifle.

Temp 73
Wind 0
D/A 2845
Lapua cases 173.2 gr.
SMK 175
43.1 grains IMR 4064
F210M
2.815 OAL
Powder dropped from Promethius and using a 10" drop tube.
All shooting prone with tight sling and small rest under left hand.

Sight dead on at 300 like the book says. No wind is best.
Shoot one shot at 100 with 300 yard setting. Should be 5/8" high. Shoot one shot at 100 on 500 yard setting. Should be 2.25" high.
Shoot at 100 with setting at 100. Should hit bullet hole you are aiming at. Varify other ranges as interest and range permit.
At 800, I stayed centered by using one unit LEFT setting on windage to offset spin drift. I shoot at a 1" dot to 400 and 2" dot to 800. My MST was not clear enought to do this at first, as I could not get it focused. I shipped to USO and it came back clear as a bell. Took about 10 days.

I really like this rig and though I know that most will disagree, I find it a very effective, simple, tough set up for putting a bullet on a spot to 900 yards. I will get to the farm and shoot to 1000 soon as the crops are out.
Very little to adjust, keep tight, or fool with. I have many high tec rifles with but this is about my favorite for just getting a bullet on a spot.
 
#593
Re: M40a1 build guide

The rings and base are USO, beautiful rifle!
The McMillan site page for the rifle mentions that McMillan barrels were put on M40A1s along with other brands. The list of barrel brands used over the years is interesting!

The ad mentions that the m40a1 revolutionized the modern tactical rifle, well don't forget the SSG69 that came first, but since the SSG69 doesn't hold a candle to the M40a1 in ruggedness or repeatable accuracy, the a1 is the standard by which all others are judged.
 
#594
Re: M40a1 build guide

First off im not here to piss anyone off!!!! Im a 2112 Precision Weapons Repairman at Quantico Va. Ive talked with quite a few people about this and I can say this, The lug and barrel stamped with a serial number is not the spec. Im not saying this is wrong because theres was really no spec when it came to this. They may have stamped the lug and barrel at one time but again this was not a spec. Its whatever the guy building the rifle wanted to do. So if you want to get technical there would have been various specs. Let me give you an example, When i became a 2112 we were stamping the A3's and The beginning A5's with the year and month it was built on the barrel. This made no sense to me what so ever so I recommended we stop and so we did. This served no purpose because the gun book would give this data. We were also stamping the bolt handle in various locations and i made the recommendation to just stamp it on the upper top part of the bolt so it looked alot cleaner. So like I said im not saying the serial number and lug stamped with the number is wrong. That was just not a spec. The spec were from the TDP or the drawings or blueprints we call it. So before you get your panties in a wad how bout you ask for an explanation. If you know Eric Reid hes a coworker of mine. He knows my credentials and we have talked about this. Also went out and met with Bill Wiseman for a few days. If you know Bill Wiseman helped develop the A1. Ive also built enough guns to know what im talking about.
 
#595
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JR CARTER</div><div class="ubbcode-body">First off im not here to piss anyone off!!!! Im a 2112 Precision Weapons Repairman at Quantico Va. Ive talked with quite a few people about this and I can say this, The lug and barrel stamped with a serial number is not the spec. Im not saying this is wrong because theres was really no spec when it came to this. They may have stamped the lug and barrel at one time but again this was not a spec. Its whatever the guy building the rifle wanted to do. So if you want to get technical there would have been various specs. Let me give you an example, When i became a 2112 we were stamping the A3's and The beginning A5's with the year and month it was built on the barrel. This made no sense to me what so ever so I recommended we stop and so we did. This served no purpose because the gun book would give this data. We were also stamping the bolt handle in various locations and i made the recommendation to just stamp it on the upper top part of the bolt so it looked alot cleaner. So like I said im not saying the serial number and lug stamped with the number is wrong. That was just not a spec. The spec were from the TDP or the drawings or blueprints we call it. So before you get your panties in a wad how bout you ask for an explanation. If you know Eric Reid hes a coworker of mine. He knows my credentials and we have talked about this. Also went out and met with Bill Wiseman for a few days. If you know Bill Wiseman helped develop the A1. Ive also built enough guns to know what im talking about. </div></div>

Carter,

I appreciate you shedding some light. It sounds like a lot of tribal knowledge and less verified facts. Is there a list of specs that you can share regarding the a1's specifically? I don't want anything that could potentially be classified, but this build guide was started to help those of us weekend warriors get it right. Thanks again.

jeff
 
#599
Re: M40a1 build guide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sheldon</div><div class="ubbcode-body">Got most of it off with the lacquer thinner. Will try to post some before and after pics later. I'm hoping to drop in a .22 rimfire 40X into mine.</div></div>

For now I'm also going to put my Rem40XB HB .22lr rimfire trainer into my return stock with matching bottom metal.


<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rth1800</div><div class="ubbcode-body">I have done some more range test with the full spec clone and MST 100. Barrel is 24" from front of lug to end. TBA rifle, Schneider barrel. USO USMC mount.
I have found that the following load will shoot exactly on the settings to 800 yards.
This is a top end load and should be worked up to, I am calling it Max in my rifle.

Temp 73
Wind 0
D/A 2845
Lapua cases 173.2 gr.
SMK 175
43.1 grains IMR 4064
F210M
2.815 OAL
Powder dropped from Prometheus and using a 10" drop tube.
All shooting prone with tight sling and small rest under left hand.

Sight dead on at 300 like the book says. No wind is best.
Shoot one shot at 100 with 300 yard setting. Should be 5/8" high. Shoot one shot at 100 on 500 yard setting. Should be 2.25" high.
Shoot at 100 with setting at 100. Should hit bullet hole you are aiming at. Verify other ranges as interest and range permit.
At 800, I stayed centered by using one unit LEFT setting on windage to offset spin drift. I shoot at a 1" dot to 400 and 2" dot to 800. My MST was not clear enough to do this at first, as I could not get it focused. I shipped to USO and it came back clear as a bell. Took about 10 days.

I really like this rig and though I know that most will disagree, I find it a very effective, simple, tough set up for putting a bullet on a spot to 900 yards. I will get to the farm and shoot to 1000 soon as the crops are out.
Very little to adjust, keep tight, or fool with. I have many high tech rifles but this is about my favorite for just getting a bullet on a spot.</div></div>

Sounds like everything's working just as it should!
 
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