View Full Version : New build Short stroking issue diagnose
Hello all,
I have a short stroking issue I want some input on.
Backstory: bought a new windham weaponry AR Orc rifle from academy sports 3 weeks ago (commercial buffer tube, carbine)
Put a few hundred rounds thru her perfectly, from cheap steel to 556.
Found a PSA FN upper I wanted and bought it with the intent of building another rifle with the windham upper.
. list:
Windham factory upper 16" carbine.
New Spikes lower
Spikes LPK
Mil spec buffer tube (carbine buffer)
Red barn armory auto BCG
(BCG’s are complete and includes carrier (8620 Tool Steel), carrier key, bolt (9310 case hardened), extractor, extractor spring, extractor pin, ejector, ejector spring, ejector pin, firing pin, firing pin retainer, cam pin, (3) gas rings, and properly staked screws. Carrier and Gas key are chrome lined.)
The gun was having issues with monarch 223 brass 55gr FMC
Once I started using my m855 and m193 it was running perfect.
So, I started thinking and I have a couple ideas.
1. Check the carrier key torque and for leaks.
2. I need to lower the buffer weight. ( can't find one lighter than the carbine buffer)
3. Need to swap the mil spec tube for a commercial one, .5" longer.
4. Leave alone and shoot mil ammo.
What's your thoughts?
Thanks
The gun was having issues with monarch 223 brass 55gr FMC
This is your problem. The solution is to shoot quality ammo in the gun. You fixed your own problem by shooting M855. Continue to do so and you will have no issues.
4. Leave alone and shoot mil ammo.
This would be my vote.
Do you have access to a chronograph, so you could provide us the muzzle velocity of the Monarch 55g ammunition?
Neg on the chrono.
But, this "issue" makes sense, since the gun is set up to mil spec and only having issues with non-mil spec ammo.
The way I see it now is, if one wants to be able to shoot commercial ammo, one should setup their rifle with a commercial buffer and semi BCG(although, my 1st rifle works with the auto).
polymorpheous
09-03-13, 12:32
Make sure the BCG is well lubed.
Put 1k of 5.56NATO pressure ammo through it.
Then try the cheap range fodder.
I bet you have better results.
The Monarch stuff is particularly low-pressure, even for .223 in my experience. PMC .223 is closer to 5.56 pressure and runs very consistently in my guns. I agree with the above poster that a well-lubed gun with 1,000 rounds of 5.56 through it may have loosened up enough to run the lower pressure .223.
I wouldn't recommend setting the gun up to run lower pressure stuff. The reason your Windham upper does so is that it is over-gassed. Bushmaster/Windham and most other "commercial" AR manufacturers oversize their gas ports so they will run with weaker ammo and they won't get all the consumer complaints from guys who don't know any better.
3. Need to swap the mil spec tube for a commercial one, .5" longer.
What's your thoughts?
Thanks
Not sure what you're describing here, but the buffer tube / receiver extension isn't your problem. As has been stated, it's an ammo issue. How did you lubricate the upper?
Not sure what you're describing here, but the buffer tube / receiver extension isn't your problem. As has been stated, it's an ammo issue. How did you lubricate the upper?
Drenched in lube for break in. CLP
As what I mean about swapping tubes, with the commercial tube, springs and buffer weights being the same, the mil-spec is .5" shorter, so the spring is being compressed more, so it would take the higher pressure to push the BCG back far/long enough.
So if I switch to a comm. tube, it will not take the high pressure of 556 to run.
The Monarch stuff is particularly low-pressure, even for .223 in my experience. PMC .223 is closer to 5.56 pressure and runs very consistently in my guns. I agree with the above poster that a well-lubed gun with 1,000 rounds of 5.56 through it may have loosened up enough to run the lower pressu
I wouldn't recommend setting the gun up to run lower pressure stuff. The reason your Windham upper does so is that it is over-gassed. Bushmaster/Windham and most other "commercial" AR manufacturers oversize their gas ports so they will run with weaker ammo and they won't get all the consumer complaints from guys who don't know any better.
I called Windham and found that the upper is NOT over gassed, it has the same diameter port as a 16" Colt, .063.
You are putting out bad/in-correct info about Windham and probably BM. Not cool man.
Windham is actually putting out very nice guns that are on Par or Better than the other high end AR rifles, they're QC is impressive, I have researched it plenty, go see for yourself.
Also, if it was over gassed, that would help the short stroke issue.
But I do appreciate your input.
Drenched in lube for break in. CLP
As what I mean about swapping tubes, with the commercial tube, springs and buffer weights being the same, the mil-spec is .5" shorter, so the spring is being compressed more, so it would take the higher pressure to push the BCG back far/long enough.
So if I switch to a comm. tube, it will not take the high pressure of 556 to run.
Measure the inner length of the tubes, not the exterior. Commercial and mil-spec are the same.
Make sure the BCG is well lubed.
Put 1k of 5.56NATO pressure ammo through it.
Then try the cheap range fodder.
I bet you have better results.
Yep. With a new firearm if I have it well lubed, use quality mags & ammo, I usually don't fret if I have a malf or 2 at first. Just the individual parts becoming familiar with each other. My last firearms purchase was a M&P 22 handgun that had problems going into battery. Ammo used was CCI Tactical. After about 350 rounds & some manual cycling it runs like a top now.
My last AR build is a super soft shooter. A5 w/A5H3 buffer, green springco, middy 14.5 DD, & LMT enhanced carrier. It too at first wouldn't cycle PMC bronze 100%. After some break in time with M193/M855 it will cycle everything I load in the mag well. IMO this break in period is even more critical with a parts bin gun sometimes. I have no experience w/Monarch ammo but if my middy's will run bronze & Tula (& they do) without issue then I am a happy camper.
Shoot some 5.56 through it for a while. Keep it lubed and see if the problem persists IF your gas rings, gas block, tube, & key are good.
Your upper won't need a lighter buffer. I guarantee you it's got plenty of (read, too much) gas hitting that carrier key. Especially w/it being a 16" barrel.
-Jax
I called Windham and found that the upper is NOT over gassed, it has the same diameter port as a 16" Colt, .063.
You are putting out bad/in-correct info about Windham and probably BM. Not cool man.
Windham is actually putting out very nice guns that are on Par or Better than the other high end AR rifles, they're QC is impressive, I have researched it plenty, go see for yourself.
Also, if it was over gassed, that would help the short stroke issue.
But I do appreciate your input.
How many gas ports have you measured? Have you actually measured the one on your gun? The commercial grade manufacturers like Windham (who is Bushmaster all over again) are notorious for putting out bad info about their rifles, intentionally or otherwise.
Not sure if you meant to type what you did in your last sentence, but yes, over-gassing would help the short stroke issue. Hence, my reasoning as to why you didn't have issues running the low pressured ammo in your Windham gun.
Please quantify what you found in your research that lead you to make the bold/italic statement. I'll tell you on the front end that fit and finish don't count towards a properly-functioning AR.
I'm not trying to pick on you or your weapon, but step back and take a look at the situation objectively:
You own a Windham, therefore you are likely to defend it. You're already "invested" in your purchase emotionally.
Those of us that have knowledge of such things and have been around AR's for awhile know the sort of games that these manufacturers play and can tell you the facts from experience as to why certain manufacturers are more highly regarded than others. It has nothing to do with the name. Another example of such mis-leading info from manufacturers in with regard to chamber spec. Bushmaster was notorious for marking their barrels "BMP 5.56" Guess what, the barrels were MPI'd @ a few per batch, not every barrel. Also, their chambers weren't 5.56 as revealed by a chamber reamer.
So, I'd caution you against blindly believing what a manufacturer tells you on the telephone.
You have no idea what you are talking about. Second thing is that MILSPEC tubes and commercial tubes are the same length, its the diameter that is different. If you are saying the tube it is a 1/2 longer then it is wrong. In my Houston class one of the guys brought a new WW carbine to the class that had similar issues. We discovered they put an AR10 tube on the carbine. Coupled with a spring that was only 10.5" and light buffer its sounds almost like your current issue.
I called Windham and found that the upper is NOT over gassed, it has the same diameter port as a 16" Colt, .063.
You are putting out bad/in-correct info about Windham and probably BM. Not cool man.
Windham is actually putting out very nice guns that are on Par or Better than the other high end AR rifles, they're QC is impressive, I have researched it plenty, go see for yourself.
Also, if it was over gassed, that would help the short stroke issue.
But I do appreciate your input.
Drenched in lube for break in. CLP
As what I mean about swapping tubes, with the commercial tube, springs and buffer weights being the same, the mil-spec is .5" shorter, so the spring is being compressed more, so it would take the higher pressure to push the BCG back far/long enough.
So if I switch to a comm. tube, it will not take the high pressure of 556 to run.
CLP is mediocre at everything it's designed to do in my experience.
Drenched in lube for break in. CLP
As what I mean about swapping tubes, with the commercial tube, springs and buffer weights being the same, the mil-spec is .5" shorter, so the spring is being compressed more, so it would take the higher pressure to push the BCG back far/long enough.
So if I switch to a comm. tube, it will not take the high pressure of 556 to run.
Commercial tubes are a different exterior diameter and material, but are not different in length and have no effect on the gas drive or cycle of operation as a stand alone part. The vltor A5 system is the only exception to this rule.
ETA - IG beat me to it.
Ah, didn't measure the lentgh inside, just outer length.
Comm. 7.8"
Mil 7.25"
Hence .5" difference, and you can see it when both stocks are collapsed, the mill tube sits in the stock .5" more than the commercial does.
As for the windham functioning with the monarch, your correct, but now that same upper wont shoot monarch with the new spikes lower its on.
I put a PSA FN upper on th windham lower.
Then built a spikes lower and put it with the windham upper(this combo is one we are talking about).
So, if the length of travel is the same for mil and comm tubes, despite the comm tube being .55" shorter, I'm puzzled why the upper wont shoot ammo it shot befor the lower change.
I've actually seen commercial tubes that are slightly longer on the exterior, because the back end is angled. This is why the Magpul CTR for commercial buffer tubes had a thicker pad. However, the interior length is identical.
Ah, didn't measure the lentgh inside, just outer length.
Comm. 7.8"
Mil 7.25"
Hence .5" difference, and you can see it when both stocks are collapsed, the mill tube sits in the stock .5" more than the commercial does.
As for the windham functioning with the monarch, your correct, but now that same upper wont shoot monarch with the new spikes lower its on.
I put a PSA FN upper on th windham lower.
Then built a spikes lower and put it with the windham upper(this combo is one we are talking about).
So, if the length of travel is the same for mil and comm tubes, despite the comm tube being .55" shorter, I'm puzzled why the upper wont shoot ammo it shot befor the lower change.
If you kept the same bolt carrier group and all upper components the same and just swapped onto a different lower then the only variable is the action spring (and arguably the buffer weight, but you said they're both carbine). Perhaps a longer/stronger action spring in the Spike's lower you built, hence the short stroking? IG gave evidence above of a WW rifle being shipped with a min-spec length action spring.
If you kept the same bolt carrier group and all upper components the same and just swapped onto a different lower then the only variable is the action spring (and arguably the buffer weight, but you said they're both carbine). Perhaps a longer/stronger action spring in the Spike's lower you built, hence the short stroking? IG gave evidence above of a WW rifle being shipped with a min-spec length action spring.
Springs are the same length.
I bought a new BCG for the windham/spikes build, it is an auto, like my original.
The Monarch stuff is particularly low-pressure, even for .223 in my experience. PMC .223 is closer to 5.56 pressure and runs very consistently in my guns. I agree with the above poster that a well-lubed gun with 1,000 rounds of 5.56 through it may have loosened up enough to run the lower pressure .223.
I wouldn't recommend setting the gun up to run lower pressure stuff. The reason your Windham upper does so is that it is over-gassed. Bushmaster/Windham and most other "commercial" AR manufacturers oversize their gas ports so they will run with weaker ammo and they won't get all the consumer complaints from guys who don't know any better.
This is very good advice. Apply a generous amount of lube, break in the rifle and you may be able to shoot the lower pressure commercial ammunition after the rifle wears in enough.
The problem is that you don't have the requisite experience and knowledge to correctly troubleshoot this.
Have you thoroughly inspected the rifle? Do you know if the carrier key is leaking? Do you know for sure that the gas block/FSB is not leaking? Do you know for sure that the gas tube and everything else is correct?
If not, then you are going to be pissing in the wind.
Springs are the same length.
I bought a new BCG for the windham/spikes build, it is an auto, like my original.
Springs are the same length.
I bought a new BCG for the windham/spikes build, it is an auto, like my original.
Put the original bcg back in the Windham upper and see if it runs. If it does you've isolated the issue down to the new bcg. Check the key for movement, ensure screws are tight/staked. Check key for obstructions. Ensure rings on the new BCG are sealing properly (put bolt in forward/unlocked position and stand the carrier on the head of the bolt. If the weight of the carrier is enough to compress the bolt, you need new rings).
Nevermind... ASH beat me to it.
On second thought, if it runs fine with 5.56 ammo as you said in your original post, shoot the gun some more with quality ammo and make sure it runs. No reason to replace working parts to make the gun shoot crappy ammo...that's called chasing a ghost.
On second thought, if it runs fine with 5.56 ammo as you said in your original post, shoot the gun some more with quality ammo and make sure it runs. No reason to replace working parts to make the gun shoot crappy ammo...that's called chasing a ghost.
I'm going to swap BCG's next, if it still has issues with the cheap ammo, I will just keep using the 556 and see what happens after a case.
Im Positive the FSB isn't leaking and you all say the tubes are the same, springs are the same, so the BCG is the difference.
Both BCG's are basically new and bolts and rings are too. And the staking and key are not moving or blocked, Mia-aligned
I'm going to swap BCG's next, if it still has issues with the cheap ammo, I will just keep using the 556 and see what happens after a case.
Im Positive the FSB isn't leaking and you all say the tubes are the same, springs are the same, so the BCG is the difference.
Both BCG's are basically new and bolts and rings are too. And the staking and key are not moving or blocked, Mia-aligned
It's possible that the new BCG just needs a little breaking in, which can be accomplished by running a few hundred rounds of good 5.56mm ammo through it. Do you notice any more resistance when moving the bolt in the new BCG? I have found that some of my uppers become more ammo tolerant over time as the parts break in.
It's possible that the new BCG just needs a little breaking in, which can be accomplished by running a few hundred rounds of good 5.56mm ammo through it. Do you notice any more resistance when moving the bolt in the new BCG? I have found that some of my uppers become more ammo tolerant over time as the parts break in.
I believe this may be it too. When I cycle manually, you can feel the drag from the new BCG, like little lines from machining or something.
It's possible that the new BCG just needs a little breaking in, which can be accomplished by running a few hundred rounds of good 5.56mm ammo through it. Do you notice any more resistance when moving the bolt in the new BCG? I have found that some of my uppers become more ammo tolerant over time as the parts break in.
Which is why I polish the railed surfaces on the BCG w/220 grit sandpaper. Makes the interface b/t the upper and bcg MUCH smoother.
-Jax
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.