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Army M24 Build Thread

Re: Army M24 Build Thread

The M24 trigger that Mike works on is the exact one that comes on the M24? Just making sure before I call on Monday.
 
Re: Army M24 Build Thread

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Early L&S ULTRA M3a 10X, and current Leupold MARK 4 M3 LR/T cartons.

One can get a feel for how special the early ULTRA optics were, and their handbuilt nature from looking at the typewriter label serial number taped onto the end panel of the shipping carton! Sort of like the handbuilt wooden boxes John Unertl used to ship his 10X USMC glass
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Re: Army M24 Build Thread

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Engraved logo on ULTRA and MARK4. Current military issue MARK 4 only has serial # with the letter "M" at the end.

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Elevation dials rotate in opposite directions on Ultra and MARK4

M118 (173gr.) cartridge dial on ULTRA, M852 (168 SMK) on MARK 4


 
Re: Army M24 Build Thread

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: USMC Grunt</div><div class="ubbcode-body">The M24 trigger that Mike works on is the exact one that comes on the M24? Just making sure before I call on Monday. </div></div>

Grunt, over the decades, Remington has made many different variations of their 700 trigger. Some have an adjustment screw located forward of the trigger. They actually made a trigger that could be adjusted down to 2 ounces, for the M40XB-BR (BenchRest) that did not include a safety lever! I could be wrong, but chances are Lau adds the rear spring pad onto a standard 700 trigger, and drills/taps the shoe for the adj screw and spring?
 
Re: Army M24 Build Thread

Strike 33 Series chassis for 700 long action
NewCadexStrike33.jpg



It can be ordered in Black and Flat Tan

Comparing it to the M24E ESR

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Also we carry the Rangemaster Tracker Sights as well.
 
Re: Army M24 Build Thread

You are correct that Lau adds block to the rear of the sear and then bores a hole for the set screw. Remington takes the 700 trigger and replaces the 700 sear with a sear made specifically for the M24. This part cannot be had unless you have a Remington M24.

As for the trigger with the adjustment screw forward of the trigger is also a 40X trigger which was not used on the M24.
 
Re: Army M24 Build Thread

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Comparison between regular H-S Precision buttstock recoil pad thickness and military issue M24 pad. The Army specified a shorter LOP which required a thinner pad.
 
Re: Army M24 Build Thread

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Civilian markings have "H-S PRECISION" molded into the pad, military has "Remington"
 
Re: Army M24 Build Thread

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Steel floorplate on the M24 was originally designed by Pete Greisel of Dakota Arms. Sunny Hill Manufacturing purchased Dakota Arms in April 1989, and has supplied Remington since.
 
Re: Army M24 Build Thread

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MagnaFlux proof test markings as required by the Army. Bolt, floorplate, and bbl. Some of the earliest M24's also had their bolt shroud marked with the Circle "M", but recent examples lack this proof.

The barrel actually has 2 seperate MagnaFlux proofs: one in a small triangle that signifies the 1st inspection, and then the CircleM that signifies testing after a high-pressure proof round has been fired.
 
Re: Army M24 Build Thread

Nice piece of information for those out there that don't know the history. One caveat to that, the Dakota floormetal is a two piece construction that is welded together and the Army spec required Remington to magnaflux the weld and then Remington stamped an "M" inside a circle right side forward of the trigger guard. The Sunny Hill floormetal is not welded but screwed together with 2 allen screws and eliminated the need for the the magnaflux inspection.

Early floormetals were coated in RemTough to match the barrel and receiver but they scratched and chipped so bad that Remington discontinued the RemTough finish on the floor metal.
 
Re: Army M24 Build Thread

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Issue sling swivels are Uncle Mikes Q.D. 1 1/4"" mil-spec stainless with SwivelLock feature to prevent accidental opening. Lovingly handcrafted in China by skilled artisans working under the masterfull eye of Hattori Hanso
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Sling is the venerable M1907 pattern leather. These items are often replaced by the individual soldier to their preference.
 
Re: Army M24 Build Thread

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Original issue bipod was the Harris Ultralight 1A2, and every version of operator manual details its functioning. Specifically, the legs <span style="font-style: italic">retract</span> when the release lever is pushed. Other Harris bipods work the opposite, <span style="font-style: italic">extending</span> the legs when the release is pushed (Model SLM for example). Also illustrated in all OM's are the early production foot pads, made from hard plastic. Newer Harris bipods have larger rubber footpads installed.
 
Re: Army M24 Build Thread

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M24 bolts are mated to the receiver, serial number stamped on underside of handle. The application of different coatings is visible. Dull finish area is Sandstrom Products MBD. Black finish is proprietary Remington Rem-Tough. Sandstrom is used to eliminate binding/galling inside receiver contact surfaces.
 
Re: Army M24 Build Thread

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Action screws are Stainless Steel 5/32" allen-head(regular carbon steel shown for comparison). Seekonk calibrated torque wrench Model [email protected] is issued with M24 deployment kit. It is also used for ring mounting nuts.
 
Re: Army M24 Build Thread

Lockedandloaded that is great info you posted there. Didnt know all that. One thing that I have been asking but no one knows is the SN markings thats on the bolt. Do they mark them the same way that the USMC does on their sniper rifles (bolt, trigger guard, floorplate, and scope mount)?

Also the torque wrench, are the trigger guard screws and the ring mounting nuts they are torqued to 65 in lbs?
 
Re: Army M24 Build Thread

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: USMC Grunt</div><div class="ubbcode-body">Lockedandloaded that is great info you posted there. Didnt know all that. One thing that I have been asking but no one knows is the SN markings thats on the bolt. Do they mark them the same way that the USMC does on their sniper rifles (bolt, trigger guard, floorplate, and scope mount)?

Also the torque wrench, are the trigger guard screws and the ring mounting nuts they are torqued to 65 in lbs? </div></div>

The serial # only appears on the bolt handle, nowhere else. Not even on the buttstock. I've seen rebuild numbers/letters stamped onto the inside of the floorplate, but not the serial #. Will look for a photo of that and post it.

65in/lbs torque on action and ring nuts. Dont have any specs for the base bolts or cap screws, but it should be much lower due to their size.
 
Re: Army M24 Build Thread

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Partially obscured are some identifying stampmarks to the inside floorplate on this particular NYANG-owned M24. Not clear enough to read what they are, but might be indications for the rifle having a rebuild, or rebarrelling, at some time during its life? I've run across this same rifle many times over the years whenever the local ANG sets up a recruiting display at gunshows or county fairs. I'll be sure next time I fingerfuk it to photograph these markings
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Re: Army M24 Build Thread

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Issue sling swivels are Uncle Mikes Q.D. 1 1/4"" mil-spec stainless with SwivelLock feature to prevent accidental opening. Lovingly handcrafted in China by skilled artisans working under the masterfull eye of Hattori Hanso
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</div></div>

Point of order on the sling swivels. Though Uncle Mikes may market their sling swivels as "Mil Spec", they weren't issued by Remington on the M24. The swivels used by Remington may be made by Uncle Mikes under contract but they aren't available except through Remington. They are similar to commercial swivels but they are all steel, they are zinc phosphated grey and they have the Remington R trademark on them.

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Re: Army M24 Build Thread

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: USMC Grunt</div><div class="ubbcode-body">Lockedandloaded that is great info you posted there. Didnt know all that. </div></div>

I agree here, you're posting a lot of great pics and some good information. I wish I had done more of this back on page 8 where I was focused on iron sights, bases, scopes and scope rings.
 
Re: Army M24 Build Thread

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: EODsix</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Issue sling swivels are Uncle Mikes Q.D. 1 1/4"" mil-spec stainless with SwivelLock feature to prevent accidental opening. Lovingly handcrafted in China by skilled artisans working under the masterfull eye of Hattori Hanso
eek.gif


</div></div>

Point of order on the sling swivels. Though Uncle Mikes may market their sling swivels as "Mil Spec", they weren't issued by Remington on the M24. The swivels used by Remington may be made by Uncle Mikes under contract but they aren't available except through Remington. They are similar to commercial swivels but they are all steel, they are zinc phosphated grey and they have the Remington R trademark on them.

IMG_0617.jpg
</div></div>


That is an awesome piece of information. Thanks. I have also seen swivels made by GrovTec, Inc. issued on M24's
In one of the gov't manuals I have, they identify the replacement swivels as being made by "Michaels". I assume they mean Michaels Of Oregon (?).
 
Re: Army M24 Build Thread

I don't think I can answer that one. The TM has the NSN# and the Part# is a Remington part number. Who makes them for Remington I can't say with certainty.
 
Re: Army M24 Build Thread

In response to your adjustable butt plate and the thinner pad, here is an interesting tid bit of info. The Army specified that the M24 rifle had to be 42 inches long in order for it to fit in the parachutist's weapon's case. Any longer and it wouldn't fit. So they made it with a 24" barrel much to the shagrin of many long range experts and they required HS-Precision to make a thinner rubber pad than their normal thickness.
 
Re: Army M24 Build Thread

I've heard the story of the parachute case so many times I'm starting to think it may be true. <span style="font-weight: bold"><span style="color: #FF0000">*</span></span>


But there is no indication from the military specifications that the rifle has to fit inside this weapons case. The only available spec is that the OAL with the stock adjusted to its minimum length be not more than 46 inches.


Detailed in the TDP is that the rifle have a LOP range from 12" to 14" for the purpose of firing, while wearing both Arctic Cold Weather enviornmental clothing (with the exception of the outter arctic mitten) AND the NBC protective suit. What that means is the specs didnt require the adjustable stock for each individual soldiers firing comfort, but rather for being able to operate the weapon wearing two layers of combat clothing!




<span style="font-weight: bold"><span style="color: #FF0000">*</span></span> Came across this article written by Mr. Richard Boucher titled "Response To Sniper Gripe" on SniperCountry.com website. He mentions the 1950 weapons container and the M24 being designed to fit.

His response was a reply to another article authored by SSgt Steven M. Barry

Thanks to member Sinister for mentioning this in the next post
 
Re: Army M24 Build Thread

A field training exercise (with static-line parachute jump) was a prerequisite to the Special Operations Target Interdiction Course (SOTIC, now the Special Forces Sniper Course) through the early 2000s (I don't know if it still is -- Rick Boucher would know).

Those jumps required the students to place their M24s in the M1950 weapons case.

My (military free fall) sniper teams chose instead to rig their M24s and M21s "Exposed," i.e., no weapons case, but with a padded scope cover much like the ones Eagle developed).
 
Re: Army M24 Build Thread

Correct me if I'm wrong but you don't ever use weapons cases when doing freefall because they make an airfoil surface that would severely affect your fall?
 
Re: Army M24 Build Thread

Talking about the barrel here, being that it is 24 inches long. Is that measurement taken from the recoil lug like the USMC does for a total overall length of 25 inches or is the M24 overall barrel length 24 inches?
 
Re: Army M24 Build Thread

The 24" barrel is measured from the end of the breech, essentially from just forward of the bolt locking lugs.
 
Re: Army M24 Build Thread

Thanks EODsix, Lockedandloaded and others for more great info and pics!
I wonder if Grovtec ever supplied sling swivels to BlackHawk ind for selling under their brand? I've seen Blackhawk swivels that look just like Grovtec GT swivels. Grovtec "milforce" look very similar to Michael's "milspec," I can see the two getting confused.
 
Re: Army M24 Build Thread

I reread the above post that says that SunnyHill supplies Remington with the oberndorf style bottom metal. I speculate that means the "Dakota Arms #510" unit sold after market from various vendors is a Sunny Hill product rather than mfg by Remington. At any rate what I want to know is, is the Dakota #510 incorrect for the issue M24 because the SunnyHill unit has a thicker metal trigger bough than what I see on the Dakota Arms #510. The unit is specifically labeled as Dakota Arms by various venders. I was thinking that later issue rifles definately had a beefier bottom metal on them while earlier rifles had the lighter one. If Pete Greisel designed the unit specifically for the M24, well it seems to me that the thinner #510 unit may never have been used. I'm a bit confused.

Actually maybe no longer confused after reading SunnyHill's website. They sell #510 contoured and #514 military. Well that answers that question but I wonder if the military #514 was always the bm on issue M24s or if #510 was used on early M24s. The reason I ask is because on early rifle pics from Remington it seems to be a thinner "contoured" bottom metal and later rifles definatley have the beefier #514 trigger guard.
 
Re: Army M24 Build Thread

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Magazine follower comparison. Upper is M24 cast metal long action, lower is stamped sheet metal short action
 
Re: Army M24 Build Thread

Cool thanks for that pic!

What of my question regarding which bottom metal(Sunny Hill 510 or 514)- is correct or are they both correct? The thinner 510 model sold by Brownells as Dakota Arms 510 seems too thin but I know of folks who purchased this for builds. The 514 differs only in that its not countoured-material removed, its left thick around the bow-was this one always the issue unit or were thinner #510 ones used on earlier rifles? The 510 is still sold but I think the 514 was discontinued.
 
Re: Army M24 Build Thread

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ULTRA windage dial on left, MARK 4 on the right. They use opposite direction rotation marks.



 
Re: Army M24 Build Thread

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pre64WINmarksman</div><div class="ubbcode-body">Cool thanks for that pic!

What of my question regarding which bottom metal(Sunny Hill 510 or 514)- is correct or are they both correct? The thinner 510 model sold by Brownells as Dakota Arms 510 seems too thin but I know of folks who purchased this for builds. The 514 differs only in that its not countoured-material removed, its left thick around the bow-was this one always the issue unit or were thinner #510 ones used on earlier rifles? The 510 is still sold but I think the 514 was discontinued. </div></div>


Have to check, good question.


eta: EODsix prob has the best info for this. The oldest Brownells on hand is Cat. #59 (2006-2007). It lists both Sunny Hill and Dakota TG's. Sunny Hill Part #514-C for Long Action, Dakota Part #510 for long action
 
Re: Army M24 Build Thread

(tinypic.com switched photos!-deleted)


Build date codes stamped onto left bbl. This M24 is from the NRA Museum Collection, and the picture is from their website.

"DR" tells the month/year of assembly:
D = September
R = 1997

Remingtons in-house dating system uses the acronym:

B L A C K P O W D E R X
1 2 3 4 5 6 7 8 9 10 11 12

The Serial# itself only identifies the year the reciever was manufactured, not the year the rifle was assembled.



(picture credit NRA)
 
Re: Army M24 Build Thread

Remington made the decision to include one of the most accurate barrel designs on the M24. It's known as the 5-R™ Pattern. 5 is the number of grooves/lands in the rifling, and R stands for "radial", or ramped, which describes the intersection between the land wall and its groove . The design was perfected by Boots Obermeyer and his family, all of them High Masters Distinguished in High-Power rifle competition. It's basis was derived from prior weapons like the AK-74, the Enfield, etc. Obermeyer refined it, and started using his personally manufactured barrels to win DCM/NRA competitions. There is plenty of info on the internet to fully describe its construction, so I wont bother going into detail. But if you get the chance to run a patch down the tube of a 5R, you will know by feel what this witchcraft is I speak of!
 
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Re: Army M24 Build Thread

The Army had the following specs during the XM-24 Sniper Trials:

<span style="text-decoration: underline">ACCURACY</span>: Fired from a machine-rest using 7.62 NATO M118 Special Ball ammunition, 10,000 rounds total @ 60 shots per hour. Cleaned, decoppered, and lubricated at 30rd intervals. Trigger adjusted to 4.0#'s, and the day optic scope removed/re-attached 20X, the results must be </= to:

200 Yards 1.3 Inches
200 Meters 1.4 Inches
300 Yards 1.9 Inches

Avg. # between <span style="text-decoration: underline">Stoppages</span>: Must be over 1400rds
Avg. # between <span style="text-decoration: underline">Failures</span>: Must be over 2600 rds
 
Re: Army M24 Build Thread

<span style="text-decoration: underline">TARGETING</span>: Distance from center of impact for 1st Target, compared against subsequent targets, must be </= to <span style="text-decoration: underline"><span style="font-weight: bold">1.086 MOA</span></span>

200 Yards 2.2 inches
200 Meters 2.4 Inches
300 Yards 3.3 Inches

(*This was supposedly where the Austrian Steyr SSG-69 rifle entry failed it's testing, due to cold bore dispersion after their barrels heated up)
 
Re: Army M24 Build Thread

A significant limiting factor in the accuracy was the ammunition used during the trials. 7.62 NATO M118 <span style="text-decoration: underline">Special Ball</span> had previously been called 7.62 NATO M118 <span style="text-decoration: underline">Match</span>. But in the early 1980's, its accuracy had been downgraded so much that they changed its designation to "special ball". Speculation is that the bullet dies used to make the round had become worn out, and the shooting scores of military rifle teams began to evidence this in high-power competitions.

Instead of the expense involved with replacing their bullet dies at Frankford Arsenal/Lake City, the US Military decided to develop a brand new cartridge using the 168gr. Sierra Match King bullet, and designated the new round as the 7.62 NATO M852



And not forgetting you Navy mutts (
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) who cherish the USMC M40A1, the Marine Corps' minimum acceptable accuracy requirement of <span style="text-decoration: underline">1.50 MOA</span> also started getting harder to retain using M118 Special Ball!
 
Re: Army M24 Build Thread

The benefits of 5R rifling are many.

A major plus is it's ability to resist copper fouling for a longer time, compared to traditional rifling. Having an odd number of lands (5) means that at any location within the bore diameter, there will not be an adjacent land on the opposite side. This helps prevent the bullet jacket from 'gilding' its copper deposits.

The radial design of the land edges is also much more relaxed, somewhere in the area of 110 degrees, compared to standard rifling of 90 degrees. This tends to prevent the jacket of the bullet from getting cut (especially longer length bullets like VLD's), reducing jacket failure.

It also increases the service life of the barrel due to lower internal stress/wear.

And cleaning the bore is much easier as a result of the lower copper fouling.

There is also a small increase in bullet velocity (approx 100fps) due to the reduced contact patch between the lands.

There is (supposedly) no sacrifice in performance over the shorter distances when compared to standard button- or cut-rifling.
 
Re: Army M24 Build Thread

I'd like to add something about the clockwise/counterclockwise knobs. The counterclockwise knobs started post 2000. Earlier Mark 4s and Ultras were clockwise and had etched glass reticles. I don't think the glass reticles were retained after 2000.
 
Re: Army M24 Build Thread

Im not certain of the time frame of events, but Leupold stopped using the etched glass reticles when they changed the name from ULTRA to MARK 4, and went to the wire reticle. Then they started using them again at a later date (late 90's?), and I believe they still have them now. But I really didnt keep up with those details for many years, so cant be positive. Honestly, there were so many newer and better designs popping up all over the place, I lost track.
 
Re: Army M24 Build Thread

I can't attest to any flip flopping back and forth either. I can tell the readers with certainty that the two M3s I pictured back on page 8 are glass reticles. The M3A is a no brainer (1991) but I confirmed with Leupold that that Mark 4 there is glass as well. It is of 1998 vintage.
 
Re: Army M24 Build Thread

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I mentioned these rings in a previous post, but just found the pic on my drive. The ring on the left is an example of the earliest known type used on the M24, made from 100% machined steel, not cast. They were only issued on the prototype/testing rigs submitted for evaluation. But all were eventually replaced by the time Leupold finalised their ULTRA product line around the same time the M24 was standardized. Visible is how the base nut lacks a collar around it like the ULTRA sample has on the right. This lack of collar caused the ring nuts to interfere with the rear metallic sight base. Also noticeable is the rougher finish, sharp edges, and machining marks that are absent on the cast steel ULTRA example on right side.

(credit to whoever took this picture, I swiped it off the internet I think Sniper Central maybe?)
 
Re: Army M24 Build Thread

Wherever did you find those prototype rings? I've never seen those before.
 
Re: Army M24 Build Thread

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User Sid13 posted this photo the other day. Its private contractors firing recently built M24's over in the sandbox. The newer style rear metallic sight bases, and 2-Piece Leupold scope bases are evident. Also, it appears the shooters have taped come-up tables inside the rear lens covers.


ETA: Sid13 messaged me this info: "The sticker in my lens cover shows ranges for mil increments for ranging human targets and angle shooting corrections."
 
Re: Army M24 Build Thread

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pre64WINmarksman</div><div class="ubbcode-body">I reread the above post that says that SunnyHill supplies Remington with the oberndorf style bottom metal. I speculate that means the "Dakota Arms #510" unit sold after market from various vendors is a Sunny Hill product rather than mfg by Remington. At any rate what I want to know is, is the Dakota #510 incorrect for the issue M24 because the SunnyHill unit has a thicker metal trigger bough than what I see on the Dakota Arms #510. The unit is specifically labeled as Dakota Arms by various venders. I was thinking that later issue rifles definately had a beefier bottom metal on them while earlier rifles had the lighter one. If Pete Greisel designed the unit specifically for the M24, well it seems to me that the thinner #510 unit may never have been used. I'm a bit confused.

Actually maybe no longer confused after reading SunnyHill's website. They sell #510 contoured and #514 military. Well that answers that question but I wonder if the military #514 was always the bm on issue M24s or if #510 was used on early M24s. The reason I ask is because on early rifle pics from Remington it seems to be a thinner "contoured" bottom metal and later rifles definatley have the beefier #514 trigger guard. </div></div>

I believe the I can answer the floorplate question. My latest Brownells catalog has the Dakota #510 LA floor plate but the IS NOT the correct one, it is not beefy enough. Sunny Hill Tactical Trigger Guard Assembly #514-C is listed twice in Brownells. One is in the white and the other is black matte but the catalog numbers are identical so that's confusing. Another interesting point is that Badger Ordnance also has a listing in Brownells that looks identical to the Dakota early issue floor metal. It too is in the white, unfinished.

Below are a few close ups of the Sunny Hill floor metal on late models M24s. Lockedandloaded has already posted some good pics of the Dakota floor metal showing the magnaflux proofmark for the welding inspection. Note that the Sunny Hill is screwed together thus eliminating the need for the magnaflux inspection.

IMG_0621.jpg

IMG_0622.jpg

IMG_0623.jpg


Point of order here too. The only stock that comes from HS-Precision ready to recieve these beefy floor metals is the PST-024. HS-Precision will not make any other model with the pillars deep enough for these pieces to fit. If you need to you might contact them to see if they would do a custom job on other models that have the addition of the Adj Cheek Rest. They might just do it but they have no plans to make other models to accept Dakota/Sunny Hill floor plates. Just the PST-024 which, I just checked their web site and it seems it's no longer available from. I'm sure they're out there somewhere but you may have to look harder.

Of course you could always get another model stock and have a gunsmith mill down the bedding pillars so that they could fit.
 
Re: Army M24 Build Thread

While we're on the topic of Floor Metal, I'll add this upgrade. Badger Ordnance makes the Army issue detachable box magazine floor metal. THIS IS NOT the DBM floor metal used on the M40A3 or A5 and is NOT the floor metal used on the M24 mod for .300 Win Mag or .338 Lapua. This is SPECICALLY designed for the M24 and the PST-024 HS stock to be a drop in, no modification upgrade for the M24. It works perfectly. This is the Badger M5 DBM M24 Sniper Rifle Drop In Triggerguard P/N 306-84. It comes with one 5 round straight stack magazine. Accuracy International makes the magazine and it is called the AE MkI .308 Winchester 5rd Magazine. No other will fit.

Shown below is the Sunny Hill on top for comparison and the Badger M24 Drop In below.

IMG_0624.jpg


Note the M24's ADL Box magazine must be removed from the reciever for this to fit. Like the Sunny Hill/Dakota stuff, this requires the PST-024 long action stock with the deeper pillar inletting or you have to do a custom fit job.

Note how the floor metal "necks down" the long action magazine well to fit the short action Mk 1 Magazine.

This mod is standard on the new M24A2 SWSs but many snipers from all over have been upgrading their older rifles with this floor metal, MARS Rails, and even other HS Precision stocks i.e. PST-013 and PST-026. They of course have the resources to do the custom inletting to get the job done.