Barrel Float How Much is Enough ?

M

mrh1958

New member
How much clearance is enough between the barrel and stock when floated? Rifle in question is a 64 action Anschutz and has a wood stock and the clearance on this set up is about .020" best I can tell. The stock seems fairly stiff, what you guys think? Thank you.
 
Many use a dollar bill pulled against the barrel. If it moves freely from action face to end of fore end it is floating. bob
 
I agree with the dollar bill test as long as the gun is resting on its forearm. You want all the weight of the barrel bearing down. In other words do not hold the gun upright or by the barrel or stock but, put it on a rest. I'd even put slight pressure down on it with a wood stock and no bedding.
 
JMHO, but particularly with wood, I prefer a little more than the dollar bill trick. The .020 you mentioned is probably fine, but I like .030 better. Ever seen a scope that visibly clears the barrel but has a mark on the bottom when it's removed? I have..several. Things move. Wood moves with humidity. Depending on the stock, some move quite a bit.
 
I have seen situations where a close float was not enough. IMO the dollar bill test is long out of date. Technically the barrel is floating, but if it touches during firing, the effect will not be good. Because the motion of the barrel, relative to the forestock is mostly vertical, I like to see more clearance under the barrel, which only shows at the forend tip. Along the sides, where it shows' I like to see more like .040. The main thing is that the gap be even. This is for wood stocks. For "fiberglass" target stocks I like a lot more. If you walk down the line at a benchrest match, I think that you will see that the barrel to stock clearances are quite generous. On the other hand, if I were planning an expensive show piece, a classic hunting rifle built on an action that was selected for its appearance and history, with a stock of highly figured, finely finished and checkered walnut, I would have the stock maker follow traditional practices, knowing that the rifle would not see much actual use.
 
mwezell said:
JMHO, but particularly with wood, I prefer a little more than the dollar bill trick. The .020 you mentioned is probably fine, but I like .030 better. Ever seen a scope that visibly clears the barrel but has a mark on the bottom when it's removed? I have..several. Things move. Wood moves with humidity. Depending on the stock, some move quite a bit.
Click to expand...

Thanks for the info Mike, I was thinking that may not be quite enough, I checked the float with the rifle set up in a rest and used a piece of 0.20" cardboard and it was a close fit, the sides have more than 0.20" so ok there I think, I will shoot it more and see what happens, I was getting some vertical stringing last time out.
 
Think about the "dollar bill trick" for a moment. If someone wonders if a barrel is free floated or not, where do you get something to test that premise? Let's assume you're at the range. Most people have a thin, flexible, and tough piece of paper in their wallet, usually a dollar, but a hundred will work just as well. But taking this test as proof that barrel has sufficient clearance is not valid. You need something thicker than a buck. Actually I prefer to use tiny balls of modeling clay when fitting a barreled action to a stock, sort of like the way engine builders use Plastigauge.
 
Remember Varmint Al?

Varmint Al published some computer models of a rifle when it is fired a few years back. They may be available if one does a search here. While the video(s) won't tell one exactly how large to make the gap, one's imagination may be prompted to figure out how large may be comfortable for them.

Pete
 
There is a good related thread

on the Texas website that is about tuners but delves into how a rifle acts when it is fired. Worth a read.

Pete
 
dependent on length and diameter of barrel. big old target barrel don't whip around as much as one of those skinny tubes on a sporter. That said I always used 2 dollar bills as a thickness gauge just for checking , when glassing an action in, about a matchbook cover worth to start. I also used to use a very thin strand of wire at the tip connected to a very low amp fuse and battery circuit the other half tied to the unit. idea being that if it wiggled more than what clearance I had it would short and blow the fuse for a visual indication that I needed more for that assembly. Kind of a poor mans two/three point barrel rig that used to be sold as a way of tuning many eons ago.
 
Pete Wass said:
Varmint Al published some computer models of a rifle when it is fired a few years back. They may be available if one does a search here. While the video(s) won't tell one exactly how large to make the gap, one's imagination may be prompted to figure out how large may be comfortable for them.

Pete
Click to expand...

English Pete, try English.
 
You must log in or register to reply here.
Back
Top