How far ahead of the receiver do you glass bed?

B

BumbleBug

New member
I thought I'd ask some of the expert 'smiths here who have done a lot of bolt action bedding jobs.

As a hobby, I've bedded a couple of dozen or so rifles, mostly sporter & some varmint rifles. I always float the barrels. I started by bedding the barrel in front of the receiver tight the length of the chamber. Then I switched & bedded an inch no matter what the caliber. The last two, I tried to bed the barrel as close too the receiver ring as possible, may be a <1/4" of the barrel tight. These shot VERY well. Of course my results are too few & imprecise to draw many conclusions, but are there some rules of thumb or suggestions or comments on this?

TIA

..bug
 
Back a few years when I was in Gunsmithing school the suggested bedding to two inches in front of the receiver and free floating beyond that. It's worked for me .
It's important to do all of the bedding properly !!
 
Out to under the chamber area only. An inch isn't enough. Two inches probably is, but may not be on a long cased cartridge. That'd be mostly the big, bruiser, magnums with close to 3" cases. Type of barrel contour makes a difference too.
And any floated barrel is a crap shoot as to whether that rifle will like it or not. Floating guarantee's nothing.
 
For 15 years I was glassing [touching] under the first inch of barrel in front of the receiver.

Then I started floating the whole barrel, no good reason..

Then I read a post by Bart Bobbitt

12-24-2015, 03:43 PM
Bart B

If the barrel has an epoxy bedding pad under its chamber area, that will happen. Proved it to me by bedding two magnum barrels (one 30 caliber, one 26 caliber) that way, then tested them for accuracy at long range. As the barrel heated up, shots strung vertically. For every 1/2 inch of bedding pad I removed, vertical stringing got less.
Click to expand...

Here too
https://thefiringline.com/forums/showthread.php?t=515995
 
I am an amateur.I don't pretend to have the experience of the pros.
I've built a number of rifles that produced pretty good accuracy.
More important,Ihave tried bedding under the barrel and chamber,and the ground it out,with improvement in accuracy.
This has been done many ways,and argued a lot.I don't claim to be the guru.

IMO,have a plan,and a reason why.Then explore it.See what you learn.

Is a modern David Tubbs rifle fully floated,or does anything touch the barrel?

There are a lot of exceptionally accurate fully floated AR's

I want absolute consistency. I want the barrel held by the receiver alone,with no other influence.
I begin with truing and squaring the receiver face.That is the foundation for the barrel..Drawn tight,flat,square,.
As the sights are typically on the receiver,I want NOTHING else influencing the interface;barrel,receiver/sights.

I use the stock as a handle for the receiver.Its job is to be married precisely to the receiver,MOSTLY to not introduce any strain or variability to the receiver when the screws are tight.

I want ALLof the clamp on the floor of the receiver at the screws,recoil lug bedded .

I see no reason to add pressure from the stock one,two,or three inches down the barrel.Look at the lever arm.On a 24 in bbl,a force,or deflection two inches out is multiplied 12 times in the oscillation..

IMO,if you have a poor connection between the barrel and the receiver,like a cracked bat...then it rattles in firing.Since the sights are mounted to the receiver,you get dispersion.
So,YES!!.If you have a loose fencepost in a hole,you can lean another post against it,providing support,or a pressure point.Then the post will flop less.
Its a patch,that worked old school,and it became doctrine.
It still works sometimes.Its still a patch.

Long ago they put scope target blocks on the barrel,or on the barrel and the receiver.
What happened? They learned it was not as good as having the mounts on the receiver.
 
Savages, I bed the nut. No particular reason, just has always worked for me.

Beyond them, I stop just in front of the recoil lug. I've always figured barrel harmonics apply to the whole barrel- no reason to exclude the last inch or two, and I free-float every barrel.

That said, we all know that barrel harmonics and the pressure "wave" that oscillates end to end through a barrel after firing is a touchy thing. I suspect that just like harmonic balancers, if one felt the desire to play with it some interesting findings could result.

My bet, is it depends on the rifle, and the specific load being shot as variations in powder type/weight/bullet weight all affect the barrel harmonics.
 
Mausers with a thumb cut get the first few inches of barrel bedded. Savages get the recoil lug and back bedded.

Jimro
 
I'm no expert but I have done several (all Remington), I go 2" ahead of the receiver with the bed, I also bed the recoil lug.
 
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