AR15 / .22LR question

[Tony Wells]

Just some ideas, as my only experience is a friends Colt HBAR. I can hear that spring go boing fairly well in his.

How much does the spring expand as it is compressed. Is the larger diameter causing a rub condition in the spring tube? That would have an effect for sure. Rough surface? Any kind of drag will cause issues in the available power that the spring can provide to absorb and give back to finish the cycle. Since this is on a collapible stock, is there any kind of lip or parting flash etc that could grab the spring?

Was this kit made for that buttstock? Is there a difference in the lenght available inside the stock for the spring among different makers?

Does the spring have plain open ends or ground closed ends. If open then just remove a 1/4 turn or less at a time.

If you cut the spring back and it becomes too short, you can make or buy a new one or put in a spacer in the butt perhaps. Not the best idea I know but workable. Just think of the shock buffers used on the 1911s, they are simply .125" thick poly of some sort.
Pierre

Pierre, since this spring is about 10" long, I can't compress it by hand stable enough to measure any growth in the diameter. When assembled, I can push the buffer all the way down until the spring is collapsed without feeling any binding.
As far as being made for this buttstock, I don't know. I have my doubts. I do not have the stock parts to compare lengths/depths of the bore. Most of the conversions I can find do not give much specific information on the products.
The spring has closed ends, but not ground. If I have to, I will order a spare and start trimming.

Not for sure is a difference in spring diameters or not, but there might be and it could have something to do with the problem.

There are 2 flavors in buffer tubes when it comes to collapsible AR stocks. Mil spec and commercial. The mil spec tubes are 0.015" wider than the commercial. Have you tried it with the spring and buffer that came with the lower?

I was also wondering, are the spring and buffer that came with the kit for a collapsible stock or a regular stock? Have you tried the upper on a lower with a standard stock?

Morgan, in the free state, the springs measure within a couple of thousandths. Either one slides freely in the buttstock with no binding. Shooting the .22LR with the .223 buffer/spring doesn't work. Never cocks, and usually stovepipes.
I do not know for a fact that this spring and buffer came specifically for use with a collapsible stock. Nor do I have a original stock to compare to.

Try a Remington viper 22 to see if it will cycle.

Al.

Al, I have tried several types of shell.....some standard, some hi-V.....granted, the hi-V do a little better, but that's not the solution. It tells me that the spring is heavy, if anything.

Thats half the problem of all rimfire problems, bad ammo.

Try some wolf or SK ammo, more expensive, not high velocity, but great ammo. If it doesn't cycle with that, you need a lighter buffer spring.

Don't think you have to use high velocity ammo, half the fun of rimfire is it's quiet and lo recoil. HV stuff ruins rimfire for me.

Agreed, Andre. It doesn't disturb the neighbors or their dogs. I haven't tried either of those, but with CCI Stingers, it did a little better.

I sure do appreciate the suggestions, guys. If anyone has the spring specs for a .22 LR conversion, I'd love to get them. Or if you have a conversion, a depth of the bore in the buttstock would help determine whether this spring is actually too long.

 

[Tony Wells]

Well, some progress on this quest. I have an original Colt buttstock in hand. Sure enough, the bore for the buffer/spring is substantially deeper than the collapsible stock. Tomorrow I will change it to the original and see how it shoots. Will also verify with .223.

Question then becomes whether to simply cut the spring to length, or what?

 

[Morgan RedHawk]

I was thinking about your kit, and I could not find any 22 conversion kits that use a buffer and recoil spring as part of their function. They are all self contained in the piece that takes the place of the bolt carrier group, leaving lower's buffer and spring alone.

Could you post a pic of what you have so we can see what we are dealing with?

Also, cycling problems are not uncommon with the 22 conversions. Most people seem to have success by polishing the feed ramp and the little guide rod inside the spring on the top of the conversion. I saw a post on (and I hope this is not a violation of the rules) ar15.com that used a bore brush attached to a cordless drill to clean out the chamber. Other common solutions are to make sure the chamber is completely free of tiny burrs and some people replace their extractor with a fancier one.

I have noticed that with all of my own AR problems (223 only and relatively few in number), the magazine has been to blame.
Also, some people say that their 22 kit only likes certain kinds of ammo. I have a Marlin 22 that will eat anything, but a 1022 that only likes 40gr CCI.

Hope this is helpful, let us know what you find out!

 

[Tony Wells]

OK....some of it is making a little sense. I do not know that the "other" buffer/spring came with the conversion, or with the collapsible stock. I don't really see how the .22 is moving either one of these springs. Almost makes sense that the short stock would come with the different buffer/spring. I just can't see how anything could move outside the bolt group and work the spring.

I did try to fire it with no buffer and spring, and it really acted no different. Think I need to go back to a working .223 and start over, figuring out what parts go with what. I didn't mix them up, but something tells me they are.

Any more pics, just ask.

 

[Morgan RedHawk]

Hmmm, the long buffer is definately for the standard length buttstock, and the short buffer is for the collapsible. If I recall, there are a couple of different buffers for the collapsible style stocks. I will pull mine out tonight and see if it is the same as yours.

Im pretty sure that the .22 conversion does not use the buffer and spring at all. Could you post a pic of the conversion kit? Are we allowed to post links to other sites on here? I could direct you to a forum just for .22 AR stuff it is allowed.

 

[Tony Wells]

I'll put up a few more pics of the conversion. It may be best if you PM the link to me.

I appreciate the assist. Many years ago, I was something of a gun nut (the good kind), handloaded and shot thousands of rounds a year. But it's been a while, and the AR's never struck my fancy. SO my knowledge is somewhat limited.

 

[Tony Wells]

The more I examine this conversion, the more I think the buffer/recoil spring is not part of it. Here are some pictures of the major components.

I am just guessing here, but the spring seems awfully long. Free length is ~9 3/4", installed it is a bit shy of 6". If you'll notice, the coils are pretty close together, so this is taking quite a bit of compression. Are there specifications on compression strength and moving mass of the bolt? It does seem stiff for a .22LR to me.

 

[Morgan RedHawk]

Sorry for the delay in my response. There has been a lot going on and I have not had much free time (I also need to get back to RayC in another thread and am week overdue..oops!).

You did not specify whether your upper is a dedicated 22 upper or a regular 223 upper with drop-in kit, so my pics may contain some irrelevant information.

I asked a buddy of mine that has some 22 ARs, and he says there are no kits that use the buffer and spring of the lower (My buffer and spring out of my collapsible stock look the same as yours, btw). So it looks like you have some spare parts...or the beginning of another AR (oh, you may say you wont build another one just because you have a couple of extra parts...people always say that...I have said it...:whistle

The 2 most common drop-in kits that are around are the CMMG and the Spike's Tactical. They are both copies of an older kit called the Ciener. They are very similar to each other, but not quite the same. In addition to the firing pin not being interchangeable, they have some visible differences. Based on the pics you posted, I am venturing that you have a Spikes Tactical kit. Here is a pic illustrating the differences in the drop-in kits:



Regardless of the make and whether it is a drop-in or dedicated upper, it seems the most common procedures for increasing reliablity is to polish, deburr, and clean a few of the surfaces (see pic below). Since you are having trouble with extraction/ejection, if this doesn't help, you could try shortening the spring that belongs with the kit a little at a time and see if that does it (they are cheap to replace if you bugger it up). The spring is the length that typically comes with the kit, though. Spikes sells what appears to be a heavier spring kit for hot loads and full auto...maybe you have one of those?



Everyone says good things about the Black Dog magazines, so if the above does not help, maybe try one of those and see if that fixes the problem.

Hopefully one of these suggestions will do the trick...keep us posted!

 

[fhp490]

Newton's law Inertia and Mass
For every action there is an opposite and equal reaction.
Try a heaver bullet before you work on the springs.
The heaver bullet will cause more pressure and create more blow back power.

 

[Morgan RedHawk]

Newton's law Inertia and Mass
For every action there is an opposite and equal reaction.
Try a heaver bullet before you work on the springs.
The heaver bullet will cause more pressure and create more blow back power.

F=ma ftw!