Modifying a new 4.4" Savage stock to fit an older 4.275" action

[DiRTY DOG]

I had a 2005 era short action 4.275" Savage 12FV in 223 Remington. I previously bedded the action and bedded an aluminum rod into the forend to stiffen it. It shot great! But I wanted to upgrade the old tupperware stock and add a detachable magazine.

A while ago, Savage changed all their short actions from 4.275" to 4.4" to accomodate detachable magazines. Today there are not very many aftermarket stock options for 10+ year old 4.275" actions, or DBM options either.

I decided to try a Bell & Carlson sporter stock for DBM for 4.4" receivers and modify it to fit a 4.275" receiver. All I needed to do was slightly elongate the 4.4" hole in the aluminum bedding block to fit a 4.275" action.

I ordered the Atlasworx DBM with a reversable bushing to fit both 4.4" and 4.275" actions. Atlasworx is located in Australia, but shipping to the US was fast arriving in about 10 days.

Northland Shooter's Supply shipped me a 24" heavy sporter Criterion prefit in 20 Practical along with a new barrel nut. I already had their action vice and wrench.

 

[DiRTY DOG]

First I had to bed the receiver into the stock. After that I could set the final depth and position of the DBM to ensure the magazine fed correctly.

I removed the factory barrel with the NSS vice and wrench, and then stripped the action and bolt for Cerekote. I installed the new barrel and set the headspace so the stripped bolt head would just barely close on a go guage.

The barreled action fit poorly in the B&C sporter stock. The heavy sporter barrel was a little too thick for the stock's sporter barrel channel, so I used 80 grit sandpaper on a dowel to remove stock material. I had to remove a lot of material to free float the barrel, mostly depth, especially at the front of the forend. Nasty void in the forend.

Once the barrel was free floated in the barrel channel, I saw that the action was not resting on the internal full length aluminum bedding block. More cutting and sanding was required around the action. And some more dremmel and sanding to free float the tang.

 

[DiRTY DOG]

I modified the stock's front receiver screw hole. It was positioned for 4.4" screw spacing. I used a drill bit by hand to elongate/shorten the hole to fit 4.275" spacing. I should have used a jig, the hole was a little messy, but nobody will see it. Maybe I'll fix it with JB Weld but it seems unnessesary.

Before and after.

After the barreled action sat flush on the aluminum bedding block, it was time to work on the recoil lug. The lug was not touching the aluminum bedding block at all, it had about a 1/8" gap between it's rear face and the aluminum bedding block. I bedded the action and recoil lug with MarineTex without too much difficulty. I've done this a few times before.

 

[DiRTY DOG]

The B&C stock inlet was slightly too narrow to accept the Atlasworx DBM mag well to fit up inside the stock. I had to remove some of the thickness of the B&C full length aluminum bedding block to make room for the DBM. I eyeballed the dimensions and started removing aluminum.

The best Dremmel bit turned out to be this super aggressive one, which easily removed chips of aluminum.

Before.

After, the shiny metal is where I removed material with the dremmel by hand.

After some careful measuring and test fitting, the DBM inletting looked like this. I removed material slightly higher than necessary in case I had to adjust the magazine height for proper feeding. Maybe I'll bed it in place later, but it fits snug as is so probably not.

 

[DiRTY DOG]

The only 5-rd 223 AICS magazine I could find was from AccurateMag. They are steel construction, and very high quality, but pricey.

I needed to set the correct DBM depth to ensure the magazine would feed correctly. It sat too deep because the rear pillar was about 1/4" too short to reach the DBM. With a longer rear pillar, and a little bedding material under the trigger guard, the DBM had something to seat against for proper fit and torque.

Starting to fit like a rifle now!

With everything assembled and in place for test functioning, it would not feed from the magazine. The original short action bolt baffle with the extended arm (travel stop) would not allow the bolt to travel back far enough to pick up a round off the detachable magazine. A new short style front baffle was an easy fix, but a problem I overlooked so I had to wait a week for a $5 part to arrive.

With the new stock and DBM assembled, the front action bolt required shortening to 1" and the rear bolt needed lengthening to 1.9". I found the right hex head bolts at ACE Hardware and trimmed a 2" bolt down to 1.9". Both bolt heads were too wide to fit into the DBM so I ground them down to original spec via a hand drill and file. I torqued the front bolt to 35 ft lbs and the rear to 25 ft lbs.

Dummy and live testing showed that feeding was 100% from AICS magazines so far. Everything fits like a glove.

 

[DiRTY DOG]

Long story short, yes you CAN transform an older 4.275" action into a newer 4.4" stock and add a modern detachable magazine with a little inletting and pillar/bedding work.

 

[DiRTY DOG]

But does it shoot?

It now has 100 rounds through the new barrel. Groups are looking good but I'd like to reduce the SD/ES hopefully once the brass is fireformed and annealed. 5-rd groups like these are common from a bipod/rear bag.

20 Practical
Criterion 24" 1:11 heavy sporter
B&C sporter stock
Atlasworx DBM & 5-rd AccurateMag
RifleBasix-1
EGW 20moa hunter rail
Leupold Backcountry rings
Leupold VX-5 3-15x44

24gr Hornady NTX
26.0gr - 27.0gr 8208xbr (4100 - 4300 fps)
Starline
cci450
seated 0.020" off the lands

Seems to like 26.0gr the best so far @ 4100 fps, but 4300 fps is enticing for a ground squirrel and rock chuck load.

 

[William Suter]

Heck of a good job there!! It sucks when your only power tools are a Dremel and a hammer. LOL! I often wish I had an hour at my old job where I had a lathe and a Bridgeport mill. Your rifle turned out looking great and looks like its also a shooter as well!

 

[AWS]

Great job

 

[crapshoot]

wtg!

 

[gtoad]

Looking very nice.
I'd say a job well done.

 

[why]

Nice write up and looks like a good job