Fazer wrote on Aug 5^th, 2018 at 11:16am:


     There is no use, corrosion-wise, to have it lower than 35-40%.   You could hook up a humidistat to shut off the de-humidifier at that point.

CHRIS
RGChristensen

It is recommended that ideal humidity/temperature for firearms is 50% RH and 70 degrees F

Similar issue with gun-stock wood.
Buy wood that has been stored in an area similar to where you live.
If you buy wood from the humid East and live in the dry West, it will shrink or vis versa unless you let it sit for a year or so before working.
Chuck

Well.....when I moved to New Mexico from Michigan, my entire collection shrunk. new and old, severely. Family furniture heirlooms split also. Now in Montana, where it has a little more humidity, but the wood on my rifles has never come back to the metal flush, especially on the guns I built out of premium wood.
Stocked a plains rifle in March here using a 10 yr. old walnut blank, and now it is amazing to see the shrinkage in summer. 
Never ending ordeal I guess.
best
kw

The finest woodworkers allow for seasonal changes due to humidity.  The lack of issues is more likely due to the lack of exposure extremes.  zIf it was preventable, the finest furniture would have been exempted centuries ago. 

I haven't had any problems running around the airid area of the west and returning to the coast, but this is not a short term issue.  Minor issues are seasonal.  Extreme cases can take a few years.

Schuetzenmiester wrote on Aug 26^th, 2018 at 11:37pm:


Actually, Nearly ALL of the professional wood workers I know of, some making musical instruments highly sensitive to changes in temp and humidity, refuse to seal the wood anywhere but on outer surfaces. This dooms them to take a number of well established methods to allow for expansion/shrinkage of unsealed wood. It also means users of wooden musical instruments have to do a lot of retuning, often after each tune.

We get to watch this incessant retuning of wooden string instruments every time our Swedish and Norwegian friends bring their violins and nyckleharpas to Colorado or we take ours to their countries. And, the sound  boxes of these wooden string instruments are made of dense, fine grained wood that has very small growth rings.

However, some makers of stringed wooden musical instruments, people with engineering backgrounds, have gone to sealing the inside of the sound boxes of their wooden musical instruments with light-weight sealants whose solid state vibrational properties are a close match to those of the wood used in these sound boxes. Note that this DOES NOT alter the thermal expansion properties of these special woods.

Your assumption about furniture makers does not apply to anything where wood must remain stable in applications where stability is highly important, eg, sound boxes of stringed wooden musical instruments. Tradition has been the limiting factor, at least as regards effects of moisture on changes in vibrational properties of wood. 

The extensive use of synthetic stocks on rifles would not have gained so much of its popularity IF everyone had properly and fully sealed ALL surfaces of their rifle stocks.

Schuetzenmiester wrote on Aug 27^th, 2018 at 12:48pm:

marlinguy wrote on Aug 27^th, 2018 at 4:18pm:


Don't recollect having heard about this before. However, there is a very well established methodology of pressure impregnation of wood with protective solutions. No idea if that was ever applied to gunstocks.

If wood is allowed to repeatedly expand and contract due to changes in temperature and humidity, over time the result is shrinkage.  That's why, for example, table tops made round in the 18th century are now so often measurably oval if not visually so.

So, I wonder, is that why old guns - and even some new ones - are stocked with the wood just a smidgen proud of the metal rather than flush with it?

Bill Lawrence

calledflyer wrote on Aug 27^th, 2018 at 4:51pm:

Quote:


A depressurized holding tank sounds sorta like a vacuum tank, doesn't it?

Bill Lawrence wrote on Aug 27^th, 2018 at 5:12pm:


Bill,

It has been my impression that most "custom" stockers have clients that want the fanciest wood they can afford, purely for appearances. Seems that using stock wood impregnated with preservatives would be outside that mind set. Maybe for military or "rough and ready" all weather stocks, but, not for bragging material. However, some of those laminated stocks may indicate a different mind set.

Furthermore, NOT a single new rifle I have ever bought had any protective coating/finish/etc. applied to the interior of stock. 

I first learned of the advantages of sealing interiors of rifle stocks from Jack O'Conner's articles way back in 1950 or 1960s. This thread is giving me impression that maybe his advice never caught on, at least with ASSRA folks.

svartkruttgris#369 wrote on Aug 27^th, 2018 at 6:04pm:

Turners and knife makers can and do stabilize the wood that they use and it will generally be very nice to exceptional examples of the wood type, because of the cost of the process and corresponding prices of the finished pieces. My suspicion of why stabilizing hasn't caught on with the gunstock folks is because the wood ends up quite a bit heavier. Not all, but most gunmakers have turned to bedding stocks with various synthetic materials and techniques for stability.

Schuetzenmiester wrote on Aug 27^th, 2018 at 7:40pm:

Agree, Bob.
More stabilizing material can flow into wood having higher porosity, which usually, but not always, also means wood that has less density to start with.

svartkruttgris#369 wrote on Aug 27^th, 2018 at 7:53pm:

Same physical process, Grisen, whether you are dealing with the formation of gas vesicles in molten magma approaching the surface, a scuba diver with nitrogen forming bubbles in the blood stream causing the bends, and with so many many other applications... which is why they call it Applied Science.   

I can't seem to quote Gris on this phone.

It is not likely one will experience severe, non reversible, non repairable wood changes on a short hunting trip.  Certainly minor changes can occur during a severe short term exposure.   

I once had a .280 Ruger 77 that tracked sideways as the barrel heated shooting 4 or 5 shots.  I tracked it down to a spot of rust on the barrel between the barrel and forearm.  Carrying it through snow covered brush the previous winter was more than it could stand I guess  . It had so much ice and snow packed and frozen between the scope and action it became a single shot     

It was not permanently damaged.  Leaving it that way waiting for spring thaw may have yielded a different result.

The basic rules of wood stability is to do the same thing to both sides; ie, plane on side, plane the other. Musical instruments are made of relatively flat material. Gun stocks are out of that catagoery.  Odd shape, fancy grain, one side inletted and the other basically flat.  No amount sealer will absolutely prevent the shrinkage mentioned moving from MN to AZ.  I doubt it was noticeable in less than 6 months or possibly a year.  The differences wood moisture content between different parts of the country is usually less than 4 percent.  The arid SW may be an acception to that.  I am not personally familiar with that area.  I notice some minor changes in our RV woodwork during seasonal changes here in the PNW.  I didn't notice any changes spending 3 weeks in the SW.

You may be correct on the use of resin Bob. I don't recall all the details of putting stocks into vacuum bags and pulling a vacuum to seal them.
I do recall they were removing the stocks before whatever finish was set up, so the exteriors could be wiped clean and not make a mess. So I'd guess if it was an epoxy resin it wasn't a quick setting epoxy, but probably something like Acraglass that takes hours to even thicken, and 24 hrs to fully set up.

Vall, I googled "vacuum chamber wood finishing" and all it came up with was resins for stabilizing.

JS47 wrote on Aug 28^th, 2018 at 10:58pm:


Agree that IF one wants to use vacuum removal, one needs really effective equipment. Perhaps best followed by pressure injection of sealant.

As regarding moving guns from high to low or low to high humidity, those are just the kinds of changes in ambient conditions that lead well known riflemen, such as Jack O'Conner , to sealing the interior wood surfaces on their rifles. Basically this means ALL the interior surfaces, which on every new rifle I ever bought in USA were totally bare wood and highly sensitive to changes in humidity. These bare surfaces also soak up sealent fluids, such as stock finishers, really well. Even more likely to result in stock warpage is stocks made from fancy wood with grain patterns far from purely straight grained. Also, remember that during O'Conner's time as gun writer, it was common to use "shims" in barrel channels to control vibration patterns, perhaps leading to increased chance that shrinkage/swelling of bare wood would result in unwanted changes of POI in precision hunting rifles. As I recall, free-floating rifle barrels was to be the ultimate solution to such problems.

If one believes the rationals given for laminated stocks, and they do sound quite correct IF done properly, then that is one more way to get really stable stocks. Perhaps the logical extreme for wood stocks.

If, one is simply trying to prevent shrinkage of stocks in purely collector guns, then the techniques and practices of major museums are highly recommended. I would presume that NRA HQ collection uses such practices.

Schuetzenmiester wrote on Aug 28^th, 2018 at 12:52pm:


If I ever had to go to a laminated stock to get better accuracy, I'd rather have less accuracy! I find nothing appealing about a laminated stock, and not sure I could even own one on a bolt action hunting rifle! I'd rather have plastic or some man made material on a hunting rifle. At least it would be lighter, and all one color!

I've seen laminated stocks made wholly of walnut with fancy outer layers that were quite spectacular.  Not cheap, I'm sure.

Bill Lawrence

svartkruttgris#369 wrote on Aug 29^th, 2018 at 3:10pm:


Since I'm not a fan of laminated, why would I want any colors? 

After working with wood for 40 years , solid and laminated . Solid wood is like a sponge it will soak up anything it comes in contact with. The reason laminated stocks are more stable is that when wood is machined into  strips , all of the tension is taken out 
Of each pcs. So when laminated together , warping is less prominent. Larger pcs. Of solid lumber always have some kind of tension. moisture will change that tension Causing warping 

Doug