CRASH! What went wrong?

[Toolndie7]

corksoakers   :) Wash

 

you keep using that word, I dont think it means what you think it means lol

 

 

[FaRKle!]

It's also important to check how far down the carrier the shoulder of the carrier goes. For example, on my PWS MK2 carrier the shoulder extends about 1/8" further than a normal LR308 carrier's (I compared it to my MWS and a CMMG MK3 carrier).

I think it'd be pretty easy to tell if the buffer is bottoming out by putting a piece of white paper in the end of the receiver extension, and then putting marker or sooting up the end of the buffer. It should leave a print if it bottoms out under normal recoil.

Edited April 13, 2015 by FaRKle!

[washguy]

you keep using that word, I dont think it means what you think it means lol

 

Sure ...you and I know   SNL way back in the day...that funny azz skit...been using that phrase ever since  lol   Wash

[survivalshop]

It's also important to check how far down the carrier the shoulder of the carrier goes. For example, on my PWS MK2 carrier the shoulder extends about 1/8" further than a normal LR308 carrier's (I compared it to my MWS and a CMMG MK3 carrier).

I think it'd be pretty easy to tell if the buffer is bottoming out by putting a piece of white paper in the end of the receiver extension, and then putting marker or sooting up the end of the buffer. It should leave a print if it bottoms out under normal recoil.

 

 

    I can see why some Manufacturers want to make components to their spec's , it makes sense in a way . Most have statements professing their Parts may not play well with others & some still don't . This is the way we have been finding the combinations of components from different manufactures that work with the three main or more , 308 AR platform. Isn't there a Pined Thread here some where ,that shows what works with what .

 

    As far as the end of the Buffer hitting the Bottom of the Receiver Extension , this particular Extension was to test hand loads , was used with my Criterion ,16" HB & had a bunch of over pressure ammo through it for testing . The bottom of the RE was inspected before I did Surgery & the was undisturbed oil on the bottom , where the Spring seats had none , but I could tell the Buffer if it hit at any time would have left some kind of mark , from all the ammo shot through it .

   I can tell you , I never cleaned the RE out , I cleaned the Buffer & spring , then re-oiled , but never cleaned the RE out .  

   I like the idea of the paper , but don't think you even need to mark the Buffer , its going to leave a mark on the paper when or if it hits it , it will show on the paper. I was going to try to paint the side of the buffer Red & use this opened up Receiver Extension & film it , just to see if I can see it movement in slow motion .

 

  I just get too curious when I'm not sure of something , I have the need to know ! <laughs>

Edited April 13, 2015 by survivalshop

[FaRKle!]

I was going to try to paint the side of the buffer Red & use this opened up Receiver Extension & film it , just to see if I can see it movement in slow motion .

 

  I just get too curious when I'm not sure of something , I have the need to know ! <laughs>

Let me know if you need a 120-240fps video camera for that. :)

[mrmackc]

Check out the rental option on this Phantom Flex 2K High-Speed Camera up to 2000 FPS. 

 

They work good to capture the cycling of firearms and other fairly high speed mechanical processes.

 

URL:  https://www.abelcine.com/store/Phantom-Flex2K-High-Speed-Camera/

 

Then you can do a RULE 1 for all of us....include the Slo-mo video!

[FaRKle!]

So I took an AR-10 action spring (brand new) and AR-15 carbine buffer and stuck it in a clear tube (one that a springco spring comes in) and compressed them both to see if the spring prevents the buffer from bottoming out. The buffer bottoms out before the spring reaches full compression. This is what I expected.

Edited April 14, 2015 by FaRKle!

[98Z5V]

Dude, really?     You think anyone would listen too you when you treat them like that?    You may be king shyte  of turd mountain around here but if you really have the answers giving them like that is a way to make sure no one listen.   Being a dick, even if it is warranted (which I cant see that it is) is no way to get your point across.

 

Yeah, really.  All the information was presented to you, and you kept looking for another source of the problem.  I got your attention, at the very, very end, though.  You wouldn't listen before that.

 

You have to understand something - arseholes that know everything show up here all the time.  Literally, all the time.  It doesn't matter to me if you own a machine shop, or anything else.  what really matters to me is how many 308AR problems you've fixed.

 

It's strange that you only got pissed off because of how i closed my post. 

 

By the way, everybody else - your buffer slams into the back of your receiver extension every time you shoot your rifle.  That's the design.  Your spring doesn't stop it, either from spring weight, or coil bind.  If the spring stopped it from spring weight, you'd never be able to lock the BCG back by hand.  if it stopped it from coil bind, you'd be replacing buffer springs every time you went out shooting.

 

That's not hypothetical...

 

ironmonster, I'm not pissed at you, in any way.  I just find it odd that you were given the reason for your current issues, and you kept looking for more reason that didn't even pertain to the situation.  I also find it odd that if I hadn't posted my very last sentence, then you probably wouldn't have said a word.  if you were offended by that, then too fucking bad.

[98Z5V]

Hey, ironmonster - I'm not calling YOU one of those arseholes.  Just want you to know that, before you go off again. We deal with the fukwads all the time. 

[survivalshop]

 By the way, everybody else - your buffer slams into the back of your receiver extension every time you shoot your rifle.  That's the design.  Your spring doesn't stop it, either from spring weight, or coil bind.  If the spring stopped it from spring weight, you'd never be able to lock the BCG back by hand.  if it stopped it from coil bind, you'd be replacing buffer springs every time you went out shooting

 

 

   If its touching the bottom of the RE , its not much or very hard . I wouldn't use the term slam . The Tubb's flat wire spring does not let the Buffer hit the bottom of the RE , it definitely stops the buffer by spring coil bind or what ever you want to call it . 

 

   Everyone has to understand that by the time the Buffer gets even close to that far back in the RE , it has slowed down a great deal , because of the Buffer Spring & loss of momentum  

 

   Just because we can compress the spring enough to have the end of the Buffer hit the bottom of the RE or a clear tube , doesn't mean it hits the bottom when fired . 

 

   As far as the Camera , my Contour video camera & my software in this Macbook can be slowed to frame by frame , should work , but I will put a white piece of paper at the bottom , just to be sure  <thumbsup>

 

 I'm going to the range today , if it doesn't piss all day like yesterday .

[washguy]

Ironmonster, any chance you can get that tube in one more turn? That's a 16 threads per inch thread size if I remember right, if that's the case you would be crashing by 1/16" maybe you could measure your dent in the receiver and see if it's about that depth? I'm just trying to think simple.

Tool is right on....if you watch the pof video or look at the install...the lip has to extend outward to make a shelf for the carrier to rest on...yours wont with it like you installed it..and the retainer pin should have been close to the end of the slot in the tube...and yes it does make a difference  too late now though    :) Wash

[survivalshop]

 Interesting results at the range today with the test of the Buffer in an 308AR DPMS Buffing system . I didn't set up the Camera , because after looking at some of my videos , it doesn't have the high enough speed to capture or may not capture the event I need .

  I used a hand loaded 168 gr. Barnes LE bullet in a LC case , I'll have to look up the loading , but I can assure you its not a limp load . The Buffer did leave a mark on the white piece of paper , but I would hardly say it slammed or even hit it with any authority , because though it did leave a mark on one side of the paper ( the Buffer side ) it didn't leave a mark on the other side . Which tells me it touched it , but not hard enough to compress the paper , so I wouldn't even say it hit the bottom to the RE. 

 

 Here's the Buffer side

 

Here's the side against the bottom of the RE, notice there is no pass through mark , if it was compressed , like if I hit it slightly with a hammer , you would see it on the other side . Like how thick is a piece of paper ? I will measure it later.

 

 I also painted the back of the Buffers Nylon bummer with red nail polish & no mark on it . It would have cracked or chipped it hit even slightly . If you don't believe me , smack a woman's nail with a hammer ,thats polished & see if it chips or cracks .

 

 Here's a photo of the paper in the bottom of the RE & at first I thought it didn't leave any kind of mark .

 

 With the slight & I mean slight marking on the piece of paper , you have to take into account that this is a very used Buffer spring , the added thickness of the piece of paper & the nail polish , I don't think It would have even left a mark at all . There is only 1/4" to play with between the Bolt locked back & the Buffer touching the bottom of the RE., so there's not much to play with . 

  This system is not unlike a lot of gas operated systems out there in Rifles , its a fine balance between weight ( mass ) & spring compression to keep them operating correctly & not punishing other components . In this case the RE, its threaded attaching point. If the Buffer slammed or hit the bottom with any kind of authority , you would get bolt Bounce & could cause FTF & FTE issues .

 

  Note that this is all DPMS Components in 308 Carbine configuration & if you are using anything else , your results , I'm sure will very .That goes for you guy's using AR 10 components in a DPMS format . Sure it works , hell I can pretty much get anything to work , but work correctly , the way it was designed , is another thing . 

 

 

 

[washguy]

Survival  you outdid yourself brother!  thanks for the effort.....so long story short..im sure there are many thousands of these rifles running just fine all over the place using what the factory intended. Its mostly when folks build one up and fall for the slick ad campaigns or the BS on the net.... just like when I was heavy into fishing...I had tackle boxes full of lures...some caught fish some didnt,but when I would walk the massive aisles in the fishing dept...I would buy more lures cause it was the latest and greatest.

Its the same motto ....the fishing lure has to first catch the fisherman....  :)  Wash

Edited April 15, 2015 by washguy

[survivalshop]

    Another thing is , the depth of the Buffer/Spring channel in the Extension , you can get varying depths & just a little difference , shorter or longer & you could have problems . This Extension is short of 7" by about a 1/16" , if it was exactly 7" the Buffer wouldn't have come close at all , well as far as hundreds of an inch  is concerned .

  I guess we need some more research on this Manufacturers Receiver Extension . Maybe like has been said , its not installed correctly or maybe the Manufacture has a specific spring & Buffer to use , I have no experience with this product ( Too Expensive for my blood )  

 

   I used to fish a lot when I owned a Boat & ya , its always the latest & greatest , but there were only a few that really worked . <laughs>

[survivalshop]

  I stand corrected , that Nail polish is some tough stuff , I smacked it with a very small hammer & it dented the stuff ,but its really on there . <dontknow>  Acetone will make short work of it though . Just surprised me that on that nylon bumper , it flexed & took a beating , even though it was a baby Hammer .

[98Z5V]

Use a 1" dowel, put some black shoe polish on the end if it, insert it into the receiver extension - and get black shoe polish onto the end of the receiver extension, inside.

 

Make sure the poly bumper on the end of your buffer is clean, and assemble parts.

 

Shoot one (1) round.

 

Remove buffer, and look at the black shoe polish on the end of your buffer...

 

When you see the black shoe polish on the end of your buffer, tell me it didn't contact the end of the receiver extension...  <thumbsup>

[survivalshop]

  Light Contact & slamming into it are two different things . That paper shows it made a very slight contact , but didn't leave an impression on it & can be seen on the opposite side of the paper . The Nail polish didn't even have a smudge on it . The bumper at the back end of the Buffer is for over travel protection , as would be in any buffer ,be it a 1911 or a 22 rifle , they all have one in some form or another . 

  Could you imagine what would happen to your sight picture if the Buffer slammed or hit the bottom of the RE every time , vibration & more felt recoil would result also . I would imagine firing a M80 Ball 149 gr. bullet would even have less recoil & not even propel the Buffer back as far as the 168 gr. load .  <dontknow>

 

 

  The paper I used was 0.004" thick.

Edited April 16, 2015 by survivalshop

[survivalshop]

 Another thing , do not confuse charging the action till it stops & compare it to the rifle firing . When you pull the charging handle all the way to the rear , there is a stop , may be the Buffer or the spring completely compressed all the way .

 I pulled the charging handle while holding pressure on the Bolt stop until it engaged & thats how I fed the round into the chamber & fired it to get my results . If you do the same test as I did & pull the charging handle all the way till it stops , it will probably hit every time , but that's not what happens when the firearm is fired . 

 

  BCG stopped with the Bolt stop

 

 Charging handle pulled till it stopped, the marked line on the RE is where the Buffer sits in the RE with out the spring installed 

[Toolndie7]

[blue109]

so does t or doesn't it?

[98Z5V]

It hits, everytime you fire it.  Everytime.

[survivalshop]

  Believe what you'all want , I have satisfied my curiosity with proof . As said , don't confuse charging the rifle with firing it . <dontknow>

 

 

  Perhaps ,someone can explain Bolt Bounce to me , causes & effects ?

Edited April 17, 2015 by survivalshop

[AngelDeVille]

One of my LGS's has AR lowers in stock for the same prices as online, minus shipping charges, so I'm heading to buy the lower for my 300 BLK project.

Edited April 17, 2015 by AngelDeVille

[mrmackc]

hit your anvil hard and fast with your ball pein hammer, the hammer bounces, now slowly touch the anvil with the hammer, no bounce, or hit the anvil with a dead blow hammer, no bounce. slowing down the cyclic closing rate of the BCG and/or using a deadblow  buffer BCG decrease the bolt bounce factor.  Most gunsmiths believe that bolt bounce has always been happening, mostly due to the inherit delay of the bolt closing rotation, but not a harmful factor with the AR pattern rifles, but wasn't noticed until ultra slo-motion photography showed that it is a fact but not something they worried about. (Delayed bolt closing is not a factor in blowback semi- and full automatic weapons) 

 

My thought is that the stripping of the unfired cartridge from the magazine and the friction of  it being chambered requires enough energy to degrade the closing cyclic velocity. There is a thin balance of energy required to complete the closing and rotation of the bolt, and slowing the closing rate to prevent bolt bounce factor.  Get the closing cycle positively completed and don't worry too much about bolt bounce until you start seeing un-natural wear on the bolt face  and chamber. Likewise to be sure the fired cartridge is completely extracted and ejected, is more important than any cosmetic damage to that fired cartridge case, unless of course the ejected case is hitting you in the face with excess energy, then start thinking about the need for a cartridge case deflector. (JMHO)  

Edited April 17, 2015 by mrmackc

[washguy]

  I stand corrected , that Nail polish is some tough stuff , I smacked it with a very small hammer & it dented the stuff ,but its really on there . <dontknow>  Acetone will make short work of it though . Just surprised me that on that nylon bumper , it flexed & took a beating , even though it was a baby Hammer .

 

 

 go ahead and leave it on...looks pretty nice!    :)  Wash