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[ARCHIVED THREAD] - Buffer Springs (Page 1 of 3)

Posted: 1/1/2006 1:02:02 PM EDT

I recently picked up a new buffer spring line from ISMI. As I pulled out my old buffer spring (which had about 8K through it) I set it down next to the ISMI spring. It looked noticeably shorter to me. I knew that buffer springs compress with use, but there was a lot of compression! So I pulled out a new CMT buffer spring and compared it against the used LMT buffer spring. It was quite a bit longer as well, but still shorter than the ISMI.

After installation of the ISMI I proceeded to double tap my way through two 30rd mags to make sure all was good. A couple rounds into the mag I noticed that felt recoil was less than with my previous spring.

So if you run between 2-3K of ammo a year through your weapon I would look at replacing your buffer springs out.

C4

www.GRTactical.com

Posted: 1/1/2006 1:07:58 PM EDT

[#1]

You just gave me a good idea.

I happen to have an new and unused CMT spring. I think I'll mark the inside of my toolbox with the length of that spring. When compression reaches 1 1/2 inches on any of my springs, time to upgrade.

Think 1 1/2 is a good number?

Posted: 1/1/2006 1:16:05 PM EDT

[#2]

Quoted:
You just gave me a good idea.

I happen to have an new and unused CMT spring. I think I'll mark the inside of my toolbox with the length of that spring. When compression reaches 1 1/2 inches on any of my springs, time to upgrade.

Think 1 1/2 is a good number?

I think 1-2 inches of compression is a good benchmark for changing. Buffer spring are cheap so it is always a good idea to have some extras.

C4

Posted: 1/1/2006 1:32:38 PM EDT

[#3]

how come the new CMT is shorter than the new ISMI ? design difference ?

Posted: 1/1/2006 1:38:27 PM EDT

[#4]

The last time I looked at a Army TM I beleive the minimum lenght is 11 3/4" with the max at 13 1/2".SJR556.

Posted: 1/1/2006 1:39:31 PM EDT

[#5]

Quoted:
how come the new CMT is shorter than the new ISMI ? design difference ?

The ISMI springs are made of Certified Aerospace Specification Materials using ISO 9002 Quality Control Standards. All Springs are Heat Treated, Shot Peened & Stress Relieved and a proprietary Design Features Enhanced Durability.

C4

Posted: 1/1/2006 1:45:53 PM EDT

[#6]

Couldn't you just strech them back out?

jj

Posted: 1/1/2006 1:49:04 PM EDT

[#7]

Quoted:
The last time I looked at a Army TM I beleive the minimum lenght is 11 3/4" with the max at 13 1/2".SJR556.

I just measured the CMT's and they are just a little over 11" and the ISMI's are a little over 12".

C4

Posted: 1/1/2006 1:50:43 PM EDT

[#8]

Quoted:
Couldn't you just strech them back out?

jj

You could, but they are worn out (compressed) and would quickly return to their shrunken state).

Springs are a cheap thing to replace and you should ALWAYS keep spare buffer springs and extraction springs around.

C4

Posted: 1/1/2006 6:41:06 PM EDT

[#9]

Owning only a lonely RRA Elite CAR-4 (mid-length), I have to ask if all buffer springs are the same length? It seems that the buffer tubes are different lengths between a fixed stock rifle and the collapsible stocks and that would seem to indicate they would use different length springs.
???

Posted: 1/1/2006 7:02:29 PM EDT

[#10]

Good info.

Posted: 1/1/2006 7:24:38 PM EDT

[#11]

Two of them are short a few coils.

Posted: 1/1/2006 9:45:32 PM EDT

[#12]

C4,
I should have noted that the minimum 11 3/4" with the max at 13 1/2"is for rifle stocks.Looking back at your first post it seems that you are referring to carbine springs.They should be 10 1/16" to 11 1/4".These are the specs for the military.I do have a carbine spring made of music wire that is much longer than the above specs that works just fine.Looking at the pics you posted your new spring looks similar to the music wire spring I have.The wire looks a little thinner and it may have more coils but they are supposed to last a lot longer.SJR556.

Posted: 1/1/2006 9:55:16 PM EDT

[#13]

Grant,

Could you try some last round bolt hold open drills with these springs? Maybe using some non-M193 rounds like American Eagle, etc. to see if everything still functions 100%? I have 2 Wolff buffer springs that I would not trust because they will not consistently hold open on the last round and gave me some ss problems.

Posted: 1/1/2006 10:06:56 PM EDT

[#14]

Was that CMT removed from a gun or from it's packaging? It's my understanding that a brand new spring is longer and will take a set after it's been installed. Not from being worn out, just getting to it's normal working length. When it's worn, it will be even shorter, more like the one on the left.

Posted: 1/2/2006 6:13:29 AM EDT

[#15]

Quoted:
Owning only a lonely RRA Elite CAR-4 (mid-length), I have to ask if all buffer springs are the same length? It seems that the buffer tubes are different lengths between a fixed stock rifle and the collapsible stocks and that would seem to indicate they would use different length springs.
???

As you can see in the above pic, the CMT and ISMI springs are different lengths, but both are for the Carbine Receiver Extension.

Carbine and A2 stocks buffer springs are diff. lengths. All carbine receiver extensions are the same length. All A2 stock receiver extensions are the same length.

C4

Posted: 1/2/2006 6:19:29 AM EDT

[#16]

Quoted:
C4,
I should have noted that the minimum 11 3/4" with the max at 13 1/2"is for rifle stocks.Looking back at your first post it seems that you are referring to carbine springs.They should be 10 1/16" to 11 1/4".These are the specs for the military.I do have a carbine spring made of music wire that is much longer than the above specs that works just fine.Looking at the pics you posted your new spring looks similar to the music wire spring I have.The wire looks a little thinner and it may have more coils but they are supposed to last a lot longer.SJR556.

The ISMI springs are a lot like the music wire springs, but differ in that they can be heat treated, shot peened and stress relieved after the spring is wound. Additionally, music wire lacks consistency from bulk lot to bulk lot.

C4

Posted: 1/2/2006 6:20:58 AM EDT

[#17]

Quoted:
Grant,

Could you try some last round bolt hold open drills with these springs? Maybe using some non-M193 rounds like American Eagle, etc. to see if everything still functions 100%? I have 2 Wolff buffer springs that I would not trust because they will not consistently hold open on the last round and gave me some ss problems.

I did already. I used UMC 55gr and M855 and both ran perfectly. I am also running a M16 Carrier and an H3 buffer.

Another thought is that you might have a bad gas seal (not getting enough pressure).

C4

Posted: 1/2/2006 6:23:51 AM EDT

[#18]

Quoted:
Was that CMT removed from a gun or from it's packaging? It's my understanding that a brand new spring is longer and will take a set after it's been installed. Not from being worn out, just getting to it's normal working length. When it's worn, it will be even shorter, more like the one on the left.

The LMT spring on the left was removed from my carbine after about 8 thousand rounds. The CMT spring on the right is brand new. From the research I have been doing, Springs compress with wear and DO compact. There was a noticeable difference in the performance of my weapon when I changed to the ISMI spring.

C4

Posted: 1/2/2006 7:33:07 AM EDT

[#19]

Springs are something that are often overlooked by people, and when springs are brought up, its almost always just the extractor spring that is talked about here.

Thanks for the info, and keep us posted.

Posted: 1/2/2006 7:45:07 AM EDT

[#20]

Grant , do you have these new recoil springs on your website yet?

Posted: 1/2/2006 7:46:18 AM EDT

[#21]

Quoted:
Springs are something that are often overlooked by people, and when springs are brought up, its almost always just the extractor spring that is talked about here.

Thanks for the info, and keep us posted.

Agree. Everyone focuses on the extractor (which is a good idea), but don't forget about the buffer.

I wonder how many shooters chamber a round and pull the trigger to only hear the worst sound in the world "CLICK!" When they pull the cartridge out of the chanber, they see where the firing pin made contact with the primer, but nothing happened. The bolt did not fully lock into the lugs.

This could be caused by many things (bad mag, dry bolt, etc). It could also be because your buffer spring doesn't have enough power to strip a round off the mag and ram the bolt home (this has happened to me).

C4

Posted: 1/2/2006 7:47:25 AM EDT

[#22]

Quoted:
Grant , do you have these new recoil springs on your website yet?

The ISMI springs are not on my web site yet. You can e-mail me for ordering instructions. [email protected]

C4

Posted: 1/2/2006 7:58:56 AM EDT

[#23]

Grant,

Are the ISMI carbine buffer springs considered to be extra power springs?

Posted: 1/2/2006 8:01:45 AM EDT

[#24]

Quoted:
Grant,

Are the ISMI carbine buffer springs considered to be extra power springs?

The company doesn't say that they are, but I would consider them to be. The have more tension than the new CMT's I have and are much stiffer. I have also experienced less felt recoil.

C4

Posted: 1/2/2006 8:32:59 AM EDT

[#25]

Quoted:
Quoted:
Grant,

Could you try some last round bolt hold open drills with these springs? Maybe using some non-M193 rounds like American Eagle, etc. to see if everything still functions 100%? I have 2 Wolff buffer springs that I would not trust because they will not consistently hold open on the last round and gave me some ss problems.

I did already. I used UMC 55gr and M855 and both ran perfectly. I am also running a M16 Carrier and an H3 buffer.

Another thought is that you might have a bad gas seal (not getting enough pressure).

C4

Many here, including SMGLee, have had problems with the Wolff springs where none existed before. Glad to here that the ISMI are not a "+10% design" and look forward to reviews by others...

Posted: 1/2/2006 8:35:59 AM EDT

[#26]

Thanks Grant. You have an email from me.

Posted: 1/2/2006 9:43:43 AM EDT

[#27]

Quoted:
Quoted:
Grant , do you have these new recoil springs on your website yet?

The ISMI springs are not on my web site yet. You can e-mail me for ordering instructions. [email protected]

C4

Thanks Grant. I appreciate the help with my issue and the great service.
Its good to have vendors like this on Arfcom to deal with.

Posted: 1/2/2006 10:00:41 AM EDT

[#28]

Grant,

was your rifle recoiling unacceptably hard or malfunctioning before you changed the buffer spring?

Posted: 1/2/2006 12:08:18 PM EDT

[#29]

Check out Tubbs site for a good tutorial on springs. Chrome silicon is the way to go, they don't take a set like music wire springs.

Posted: 1/2/2006 12:47:49 PM EDT

[#30]

Quoted:
Grant,

was your rifle recoiling unacceptably hard or malfunctioning before you changed the buffer spring?

Yes, I had some issues with it, but wasn't really sure what the problem was.

Recoil from a 5.56 is NEVER a problem, but I did notice a change.

C4

Posted: 1/2/2006 12:48:41 PM EDT

[#31]

Quoted:
Quoted:
Quoted:
Grant , do you have these new recoil springs on your website yet?

The ISMI springs are not on my web site yet. You can e-mail me for ordering instructions. [email protected]

C4

Thanks Grant. I appreciate the help with my issue and the great service.
Its good to have vendors like this on Arfcom to deal with.

Thank you for your business!

C4

Posted: 1/2/2006 12:51:11 PM EDT

[#32]

Check out my previous thread. I agree with Grant. The ISMI springs are the way to go.

http://www.ar15.com/forums/topic.html?b=3&f=118&t=248898

Posted: 1/2/2006 1:01:25 PM EDT

[#33]

www.ar15.com/forums/topic.html?b=3&f=118&t=248898

Made hot for ya.

C4

Posted: 1/2/2006 1:04:48 PM EDT

[#34]

Thanks

Posted: 1/2/2006 2:13:42 PM EDT

[#35]

Quoted:
Quoted:
Grant,

was your rifle recoiling unacceptably hard or malfunctioning before you changed the buffer spring?

Yes, I had some issues with it, but wasn't really sure what the problem was.

Recoil from a 5.56 is NEVER a problem, but I did notice a change.

C4

What were the issues?

Posted: 1/2/2006 2:15:26 PM EDT

[#36]

Ok, I'm trying sort this all out.

Has anybody used these springs with an Enendine or MGI buffer? What is the difference in this spring vs the 2X spring that MGI has?

I'm not sure which way to go once I upgrade my standard carbine spring/buffer with a new buffer and ????spring. There are so many choices and I want to get it 'right' the first time.

Thanks,

Posted: 1/2/2006 2:24:37 PM EDT

[#37]

Quoted:
Quoted:
Quoted:
Grant,

was your rifle recoiling unacceptably hard or malfunctioning before you changed the buffer spring?

Yes, I had some issues with it, but wasn't really sure what the problem was.

Recoil from a 5.56 is NEVER a problem, but I did notice a change.

C4

What were the issues?

With a 28rd mag loaded, bolt locked back I hit the bolt catch. The bolt does not fully lock into the lugs. The new spring has fixed this issue as it has more energy to slam the bolt home.

C4

Posted: 1/2/2006 2:25:33 PM EDT

[#38]

Quoted:
Ok, I'm trying sort this all out.

Has anybody used these springs with an Enendine or MGI buffer? What is the difference in this spring vs the 2X spring that MGI has?

I'm not sure which way to go once I upgrade my standard carbine spring/buffer with a new buffer and ????spring. There are so many choices and I want to get it 'right' the first time.

Thanks,

I have a Enidine in a middy and I am going to change the spring out in it as well. I will let you know how it goes.

C4

Posted: 1/2/2006 4:10:02 PM EDT

[#39]

I ran a .45 acp upper and a standard buffer spring for a few hundred rounds. It defenitely took a set. The pistol caliber uppers seem to beat up the springs more than 5.56/.223. The new ISMI buffer springs are flat wire. I have the older round coil type and it works great. I would spend the money and get one of these from Grant if you shoot much pistol cal

Posted: 1/2/2006 5:31:17 PM EDT

[#40]

So do you sell them?

If they lower recoil and last longer and also have more pressure for more reliable stripping of rounds from the mag it's a winwinwin. Why not.

Posted: 1/2/2006 5:45:26 PM EDT

[#41]

Quoted:
So do you sell them?

If they lower recoil and last longer and also have more pressure for more reliable stripping of rounds from the mag it's a winwinwin. Why not.

Yes I do. Shoot me an e-mail. [email protected]

C4

Posted: 1/2/2006 6:56:11 PM EDT

[#42]

Quoted:

If they lower recoil and last longer and also have more pressure for more reliable stripping of rounds from the mag it's a winwinwin. Why not.

The only potential "why not" is, if they are anything like the Wolff springs, they may cause a setup that formerly functioned perfectly with all types of ammo to start to intermittently short stroke/stovepipe/fail to lock back on last round, etc. But, as Grant has said, they are functioning fine for him, so until there are more results from others...

Posted: 1/2/2006 7:01:01 PM EDT

[#43]

I remember reading about a flat-wound ISMI CAR spring. Apparently, this one isn;t it. Anyone know anything about that one?

Posted: 1/2/2006 9:59:52 PM EDT

[#44]

Superior Shooting Systems markets the flat wire AR buffer springs. While I don't know for sure I'm pretty sure that SSS springs are made by ISMI. ISMI is a premium manufacture of gun springs and the use almost no BS marketing which is refreshing.

One thing to remember when you put a new spring in is that the spring will take an initial set reducing it's free length, this is 100% normal. If you have any significant reduction in free length after the initial set then look into replacing the spring. A better way to determine the state of a coil spring is to measure the compressed force of the spring. You could make a fixture out of a A2 buffer tube by drilling a hole in the butt side of the tube to the point it will capture the spring but that's about it and making a plug that has a wire or cable attached to the center of the plug. Put the spring into the tube and then put the cable down the center of the spring and out the hole. Attach a fish scale to the cable and compress the spring to a repeatable length (dremeling a slot in the side of the buffer tube and pulling the spring tight until you see the plug would work) and recored the weight.

Never pull on a coil spring it will just make it fail sooner.

All coil springs are wound in their annealed state and then heat treated, otherwise you couldn't wind them very well .

Posted: 1/3/2006 5:50:31 AM EDT

[#45]

Quoted:
Superior Shooting Systems markets the flat wire AR buffer springs. While I don't know for sure I'm pretty sure that SSS springs are made by ISMI. ISMI is a premium manufacture of gun springs and the use almost no BS marketing which is refreshing.

One thing to remember when you put a new spring in is that the spring will take an initial set reducing it's free length, this is 100% normal. If you have any significant reduction in free length after the initial set then look into replacing the spring. A better way to determine the state of a coil spring is to measure the compressed force of the spring. You could make a fixture out of a A2 buffer tube by drilling a hole in the butt side of the tube to the point it will capture the spring but that's about it and making a plug that has a wire or cable attached to the center of the plug. Put the spring into the tube and then put the cable down the center of the spring and out the hole. Attach a fish scale to the cable and compress the spring to a repeatable length (dremeling a slot in the side of the buffer tube and pulling the spring tight until you see the plug would work) and recored the weight.

Never pull on a coil spring it will just make it fail sooner.

All coil springs are wound in their annealed state and then heat treated, otherwise you couldn't wind them very well .

ISMI does make the flat spring for SSS, but advised me that there is no difference between that one and the ones I buy from them.

C4

Posted: 1/3/2006 5:52:27 AM EDT

[#46]

Quoted:
Quoted:

If they lower recoil and last longer and also have more pressure for more reliable stripping of rounds from the mag it's a winwinwin. Why not.

The only potential "why not" is, if they are anything like the Wolff springs, they may cause a setup that formerly functioned perfectly with all types of ammo to start to intermittently short stroke/stovepipe/fail to lock back on last round, etc. But, as Grant has said, they are functioning fine for him, so until there are more results from others...

ISMI springs are not 10% extra power like the Woff Springs (so you shouldn't see the same issues that Wolff springs produce). They are simply better made springs using the best materials available.

C4

Posted: 1/3/2006 8:03:34 AM EDT

[#47]

Quoted:
Quoted:
Quoted:

If they lower recoil and last longer and also have more pressure for more reliable stripping of rounds from the mag it's a winwinwin. Why not.

The only potential "why not" is, if they are anything like the Wolff springs, they may cause a setup that formerly functioned perfectly with all types of ammo to start to intermittently short stroke/stovepipe/fail to lock back on last round, etc. But, as Grant has said, they are functioning fine for him, so until there are more results from others...

ISMI springs are not 10% extra power like the Woff Springs (so you shouldn't see the same issues that Wolff springs produce). They are simply better made springs using the best materials available.

C4

Sounds great. Looking forward to more impressions...