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RP12
11-05-2013, 11:14 PM
Help me understand how it works. If for example thing are not square, how does it line everything up right ? If the lugs or action are off and the bolt head floats to correct that, then how can the cartridge be flat to the lug face and so on ? If the barrel is off, the cartridge would be off, then the lug would correct that, but then the lugs would not sit in the action squarely right ? Help this little mind figure it out, please.:confused: Or just tell me it just does, and I'm over thinking again.;)

J.Baker
11-05-2013, 11:36 PM
I think I'll wait and let Fred or someone else answer this one in detail so I can then make it an article in the Savage FAQ's.

RP12
11-05-2013, 11:39 PM
So I'm not over thinking it.;)

stangfish
11-05-2013, 11:44 PM
Fred already responded in great detail once. I will search and see if I can find it.

J.Baker
11-06-2013, 10:07 AM
So I'm not over thinking it.;)

Technically I'd say yes and no. There's reasoning and some science behind the idea of it and why it works the way it does, but you don't need to know all that - it will still do what it does even if you're ignorant to it. lol

Basically if things aren't perfectly square to one another (i.e. the barrel threads in the action aren't perfectly square to the centerline of the action or the recoil lug has some taper or the face of the barrel nut is a little out of square) the floating bolt head allows for enough angular deflection to still permit 100% contact and not create any kind of bind. Remember that we're talking about making up for a few thousandths of an inch in most cases so it's not like we're trying to overcome a recoil lug with a 5-degree taper from top to bottom or threads in the action that are 8-degrees out of square with the centerline.

Remember that these are mass production rifles, not hand made, hand checked precision rifles made one at a time. Production parts have tolerances - typically in the +/-0.015" range, and when you have that same tolerance accumulating over a number of parts (particularly in the bolt assembly) you need some wiggle room. That's what the floating bolt head provides - some wiggle room.

RP12
11-06-2013, 11:16 AM
So truing an action can help (performance wise) that condition ?

RP12
11-06-2013, 08:46 PM
Don't leave me hang'in Fred. LOL.

sharpshooter
11-07-2013, 02:42 AM
The floating bolt head insures that both lugs make contact on the lug abutments. Compared to other rifles that use a solid bolt(Remington,Winchester, Ruger, etc.) the top lug usually has little contact with the lug abutments because the trigger forces the bolt upward at the rear.
The savage bolt on the other hand, engages the cocking piece pin and the sear from the side. The "float" in the bolt head at the cross pin joint allows the bolt head to swivel enough that both lugs make contact no matter how much the back of the bolt is shifted to one side or another. The deflection at the rear of the bolt could be as much as .040" in any direction, and still get full contact on both lugs.
The receiver threads and the lug abutments are machined in the same fixture, and will always be square to one another, but may not be square to the receiver face, especially on the older models. All of the new models that have been machined on the new Okuma machining centers will have the receiver face square with the threads, although it is a milling operation, not a turning cut.

barrel-nut
11-07-2013, 09:25 AM
Thanks for the explanation, Fred. Good info for those of us who are seeking greater understanding of our rifle's unique qualities.

RP12
11-07-2013, 09:46 AM
Thanks Fred.

FW Conch
11-07-2013, 09:51 AM
The "lug" is NOT off, because it floats ;-)