Question on keeping bolt open

[efarmer21 0]

I know its probably been discussed, but I can't find anything on it via search.

 

Does leaving the bolt locked back all the time (so my shells don't deform on a closed bolt) okay in terms of not causing wear/damage to the gun?

 

I am thinking along the same lines as a mag - where it is not compression that kills the spring, but contstant compression/decompression during action.

 

Thanks in advance for your advice.

Edited September 24, 2009 by efarmer21

[saigafreake 27]

I cant see it being good on the recoil spring but i maybe wrong.

[nalioth 405]

I cant see it being good on the recoil spring but i maybe wrong.

As the OP says, it's the cycling of the spring that wears it out.

 

A spring in a constant state won't wear.

[StarPD 6]

There have been many anecdotal cases of .45 mags kept loaded since WWII that fed properly after decades of sitting that way.

As nailoth says, it's cycling of the spring that eventually causes it to weaken, not leaving it compressed.Depending on the quality and size of the spring, it can take a LOT of cycling to cause a spring to weaken. Witness the many thousands of rounds fired by some members in their S-12s.

 

So in answer to the OP's question, leaving the bolt locked back on an S-12 won't ruin the spring or lead to malfunctions.

[havok 21]

As always I will be one of the only few on this site to tell you that it's not good to do. Every spring is differant, that said, in your shotgun service manual it tells you to store the gun with hammer released to prevent the mainspring from RESIDUAL STRAIN. Residual strain will act different on different springs.

What is Residual stress/strain?

It is Stresses induced by set removal, shot peening, cold working, forming or other means. These stresses may or may not be beneficial, depending on the application.

The manual says mainspring could get residual strain/stressed ,which is not the same as a mag spring are a recoil spring.

Now I bet Izhmash has tested this many years ago, and before many of us where even able to own a Izhmash firearm. And I bet the finding from R/D says to have the mainspring released, and thats why it printed in you manual.

So the only way the hammer can be released is with the bolt closed.

 

And a mag spring can fail if not oiled for long term storage where moisture is presant. The spring can fuse/rust together.

[aresv 49]

The warnings in manuals are because compressed springs store energy. Lawyers don't want you to get hurt. That's the only reason, besides the misconception that springs take a set without being cycled.

 

If you're really worried about your recoil springs wearing out, pick up a couple of 1911 recoil springs. A pair makes a perfect replacement for the stock S-12 recoil springs.

 

If stressed steel actually creeped or moved by itself:

- old bridges would visibly sag

- old cars would all be lowriders

- the guy wires on antenna masts would go slack and have to be periodically retightened

[d5sprowln 0]

I keep my bolt open haven't had any problems. I had a lot of problem with the top round deforming even with slugs. I am a police officer and I depend on my shotgun and need it to feed at all times. I keep a mag in it at all times and this was the only way I have found to make it reliable without a lot of modifications. Before it was only a couple of days I would have to replace the top round in my mag due to deforming it would not feed. I have done the feed ramp mod described on this forum and it has helped. Also the bolt has been polished. The only spring problems I have had was my mag spring on my AGP mag broke and I kept it loaded don't know if that is what caused it.

[Antelop 33]

Fascinating thread because application seems to influence answer. For LEO or Military when weapon is in service, BHO, Mag inserted. When in storage trigger droped and bolt closed as is case for most rifles I can think of.

 

However, not sure about the constant strain theory of springs not deforming the metal. I seem to recall from College physics that even rigid solids, eventually deform under strain, its just a question of time. If I recall correctly increased entropy and quantum theory demand even solid deform over time. HOWEVER, the time scale may be too long to matter in practical application of Saiga. I think the no deformation of stress springs assumes a perfect spring, but doubt all our Saiga springs are remotely perfect. On the other hand, the Saiga was developed in the hayday of physics and engineering in Russia so on that basis, one might have confidence

[aresv 49]

When in storage trigger droped and bolt closed as is case for most rifles I can think of.

 

Bingo. Done that way for safety and cleanliness.

 

However, not sure about the constant strain theory of springs not deforming the metal. I seem to recall from College physics that even rigid solids, eventually deform under strain, its just a question of time. If I recall correctly increased entropy and quantum theory demand even solid deform over time. HOWEVER, the time scale may be too long to matter in practical application of Saiga. I think the no deformation of stress springs assumes a perfect spring, but doubt all our Saiga springs are remotely perfect. On the other hand, the Saiga was developed in the hayday of physics and engineering in Russia so on that basis, one might have confidence

 

Materials can creep under stress. It's just that steel at room temperature does not exhibit enough creep to worry about it. Steel will creep at high temperature, though: http://en.wikipedia.org/wiki/Creep_%28deformation%29

 

This spring company has a pretty good writeup about spring relaxation. Note that it's not a factor unless the springs are operating at elevated temperatures.

http://www.rockfordspring.com/relaxationofsprings.asp

Edited September 25, 2009 by aresv

[Antelop 33]

3 cheers for Aresv. His references are great.

 

For those that dont read all the references, Here are the take away points.

 

All solid materials creep or deform but phenomena is more pronounced at high temps.

The closer to melting point the more creep.

For practical application of Guns, if the springs are properly heat treated and material is good expect less than 5% creep.

 

I dont know what technical specs are for OEM springs but would guess the Russian engineers would specify heat treated creep resistant springs.

[waltham_41 52]

Get a box of Silver Bear steel cased 12 gauge shells. They only come in 7 1/2 and 8 gauge these days, but they work great for the top round as they do not distort like plastic or paper shells will. That is what I use, and my 12 rd mag has been loaded on a closed bolt for months now and will load reliably.