• Mossberg Owners is in the process of upgrading the software. Please bear with us while we transition to the new look and new upgraded software.

Glass bedded my .338 4x4

WildMatt84

Copper BB
First off here's my .338 win mag. Topped with a Nikon Buckmaster 4.5-14X40. With a caldwell bipod

null_zps3a924a4a.jpg


Well after being without my rifle for a very long time. I finally got it back from my buddy. Here are the results of the glass bedding he did for me

null_zps5dcf8f02.jpg

This is the forend with an added piece of aluminum for stiffness.Its hard to see but he also made me a completly new piece for the recoil lug. Apparently it somehow had broken


null_zpse8d7f5ee.jpg

This is the piece back near the bolt.
 
This looks very familiar to me... Have you tried other types of ammo at all? Check out my build if you haven't already. I've got some very very similar results.

Here is a target I shot pre-glass bedding, see any similarities?
E191603C-C8DE-455A-960F-6659853072C5-28546-00001D5CF9DA8A2C.jpg
 
WildMatt84 said:
the only thing thats got me stuck on it being something moving, is the amount of rise after the second shot. Thats a half decent group of 4 that is just way high to chaulk up to the barrel heating up, and then the one that dropped back down to the original 2

Nice looking set up you have there.

My first question is, how was your rifle shooting prior to glass bedding?

Though I am no expert, I have been advised by those with the expertise and experience that bedding is not always necessary for improving accuracy nor a surefire upgrade. I have been led to believe that bedding a rifle that consistently shoots decent groups should probably not be bedded as you risk skewing your accuracy.

I have been advised it's better to play and experiment with your known quantities rather than risk changing it drastically.

Don't feel bad, you wouldn't be the first guy to bed his rifle and after have real trouble getting consistent accuracy. Re-accurizing your set up can be very tedious and frustrating.

Any thoughts as to whether adding aluminum into the stock may have changed the shooting characteristics? Even heat build up and more material through which heat dispersal may take longer? Just a guess on my part.......

The .338 carries a pretty big recoil wallop, the fact that the slot for your your recoil lug was broken is testimony to that. Does your stock have any crossbolts? Large bore rifles usually come with crossbolts installed from the factory.
 
I bet it's kinda similar to the forend stiffening job I did on my .338 4x4 (also synthetic stock). I bought 3 packages of JB Weld at Wally World along with a bag of hard plastic craft beads. I drilled 1/4 holes through the forend sideways all the way through the ribbing and stock. Then I put masking tape over the holes to keep the JB Weld from draining out. And I roughened up the inside plastic with a die grinder and burr. Then I poured in the hard plastic beads so they filled in all the voids between the ribbing. Then I mixed up a bunch of the JB and slowly poured it over all the beads (I used a bamboo skewer to poke and prod them around to even it out and make sure the epoxy was flowing through the beads, not making air pockets). The beads are like gravel in concrete... filler and adds some structure to the adhesive. Anyway, it has a nice stiff forend now.

But, on to your suspected movement. What took the groups down nice and tight on mine was using JB to 'bed' the magazine holder into the stock. With the barrel/action removed, try wiggling that magazine holder piece side to side in the stock. Check both the rear and front part (near the two big screws that hold the action to the stock). I bet you'll find play there. I bedded the front part first and it didn't take much JB. After that cured (action bolted into stock with Pam cooking spray to ensure it would release from the JB) I could tip the forend down and JB the rear of the magazine holder. In the back, the JB goes in the openings to the sides of the rear action screw hole. You'll see, it's obvious.

The other thing I found with my .338 4x4 was the barrel would badly copper foul within 15 shots. It's slowly smoothing out, but it doesn't smooth out the bore unless there's no copper fouling. That means a lot of tedious copper cleaning after every few shots if your barrel is doing the same.
 
WildMatt84 said:
I think I'm gonna give my 250gr corelockts a shot at the range this weekend and see what happens

Mine shoots those like crap just FYI. Not saying it's not worth a try, as every gun is different, but I get like 4 inch groups at 100 yards with those.
 
Back
Top