Blitkrieg buffer failure

[mikeAZ]

My Blitskrieg buffer is now a 2 piece buffer. PPC gun shot once a month , not many rounds thru it, Taccom 5 " barrel w/ aluminum shrould. Rifle spring. 130 PF cronoed load. It appears that the treaded end has stripped threads and a oily mess in the tube. I've searched here (no find ) but I can remmember seeing the same failure posted somewhere?.... I'll be contacting Blitkrieg today... ANYONE else have any input?????

[longbeard]

I am always concerned of this.  I do know someone who has gone through 3 of them.

 

I also know they have a prototype for a new one.  You might ask about it and see if you get one of those as the replacement

[Tampa-XD45]

Here's another post with pics:  https://forums.brianenos.com/topic/252374-blitzkrieg-hydraulic-buffer-failure/

 

I sold mine long ago.

[mikeAZ]

WOW, TALK ABOUT CUSTOMER SERVICE!!!, Just got off the phone with Blitskrieg. Turns out, they  had become aware of some failures in the 1st. design that started showing up...There were 2 areas that have been improved. Luckly, I had purchased the buffer from them and they had my purchase date (Sept., 2017). They are sending the new version and a return tag so they may better research the failure. NOT made in China!!!

Edited December 6, 2018 by mike NM

[latenightlegend]

Yah, it's a thing. I've been through 3 of them already. The new 5015 HD version they have out is much much better than the 5007. Stiffer spring and better/more resistant hydraulics 

[longbeard]

40 minutes ago, latenightlegend said:

Yah, it's a thing. I've been through 3 of them already. The new 5015 HD version they have out is much much better than the 5007. Stiffer spring and better/more resistant hydraulics 

LOL.

You're the guy I knew who's been through three of them.  Is that 5015 publicly available yet?

 

[latenightlegend]

Just now, longbeard said:

LOL.

You're the guy I knew who's been through three of them.  Is that 5015 publicly available yet?

 

 

Buhahah, whoops 

 

It's not on the website just yet, but email Brian at info@nokick.com and ask for the 5015 HD by name. He'll sell you one! 

[HoMiE]

Use the 308 spring, mine broke when I tried a regular AR rifle spring. 

[latenightlegend]

1 minute ago, HoMiE said:

Use the 308 spring, mine broke when I tried a regular AR rifle spring. 

Always use a either a 308 Carbine/Rifle spring on blowback AR9s. 

 

These blowbacks rely on a strong spring to keep the bolt in battery. If the bolt "unlocks" too early, it'll cause a number of issues. You want the bolt the stay forward for as long as possible to keep the gasses moving forward behind the bullet. The longer the bolt is able to stay in the "closed" position, the less dot movement you will see. Also, the violent cycling of AR9s reek havoc on trigger pins. Slower, the better. A lot top GM shooters that run AR9s tend to run heavy bolts as well. Some even use a steel weight plug between the buffer and bolt in the buffer tube, as to slow down the cyclic rate. I noticed around .02-.03 slower splits with a weight. However, it's totally worth the trade off when the dot hardly moves. 

 

Hope this helps ya'll 

[HoMiE]

2 minutes ago, latenightlegend said:

Always use a either a 308 Carbine/Rifle spring on blowback AR9s. 

 

These blowbacks rely on a strong spring to keep the bolt in battery. If the bolt "unlocks" too early, it'll cause a number of issues. You want the bolt the stay forward for as long as possible to keep the gasses moving forward behind the bullet. The longer the bolt is able to stay in the "closed" position, the less dot movement you will see. Also, the violent cycling of AR9s reek havoc on trigger pins. Slower, the better. A lot top GM shooters that run AR9s tend to run heavy bolts as well. Some even use a steel weight plug between the buffer and bolt in the buffer tube, as to slow down the cyclic rate. I noticed around .02-.03 slower splits with a weight. However, it's totally worth the trade off when the dot hardly moves. 

 

Hope this helps ya'll 

[Bwillis]

2 hours ago, latenightlegend said:

Always use a either a 308 Carbine/Rifle spring on blowback AR9s. 

 

These blowbacks rely on a strong spring to keep the bolt in battery. If the bolt "unlocks" too early, it'll cause a number of issues. You want the bolt the stay forward for as long as possible to keep the gasses moving forward behind the bullet. The longer the bolt is able to stay in the "closed" position, the less dot movement you will see. Also, the violent cycling of AR9s reek havoc on trigger pins. Slower, the better. A lot top GM shooters that run AR9s tend to run heavy bolts as well. Some even use a steel weight plug between the buffer and bolt in the buffer tube, as to slow down the cyclic rate. I noticed around .02-.03 slower splits with a weight. However, it's totally worth the trade off when the dot hardly moves. 

 

Hope this helps ya'll 

Less upward dot movement 

more downward dot movement 

All being equal the 308 slams the bolt home harder

Or is that bad math? 

 

[MemphisMechanic]

20 minutes ago, Bwillis said:

Less upward dot movement 

more downward dot movement 

All being equal the 308 slams the bolt home harder

Or is that bad math? 

 

 

It’s bad math.

 

The dot is flatter and more stable period with a heavier spring. I do not know anyone who has done any amount of testing and tuning... who isn’t running a sprinco red or a .308 csrbine spring.

 

Edited December 6, 2018 by MemphisMechanic

[longbeard]

It's somewhat contrary to pistol tuning. One way to think about it is that the harder it is to move the action, the calmer the dot bounce.  Somewhere in your tuning there is a sweet spot where it doesn't completely bottom out and doesn't slam forward with excess energy.  Both of which create movement.  When you find it, the dot just stays put.

 

 

 

[HoMiE]

You’re also trying to reduce the travel in an AR9 platform since it’s much longer than a pistol. 

[Bwillis]

38 minutes ago, longbeard said:

It's somewhat contrary to pistol tuning. One way to think about it is that the harder it is to move the action, the calmer the dot bounce.  Somewhere in your tuning there is a sweet spot where it doesn't completely bottom out and doesn't slam forward with excess energy.  Both of which create movement.  When you find it, the dot just stays put.

 

 

 

That makes sense, I was basing my question off of pistol rsa and slides. Thank you 

45 minutes ago, MemphisMechanic said:

 

It’s bad math.

 

The dot is flatter and more stable period with a heavier spring. I do not know anyone who has done any amount of testing and tuning... who isn’t running a sprinco red or a .308 csrbine spring.

 

Maybe that was my issue I tested a 308 rifle spring 

Edited December 6, 2018 by Bwillis

[RaylanGivens]

4 hours ago, longbeard said:

LOL.

You're the guy I knew who's been through three of them.  Is that 5015 publicly available yet?

 

https://www.blitzkriegcomponents.com/ProductDetails.asp?ProductCode=RB5015HD

 

Quote

Blitzkrieg Components / KynSHOT 9mm AR-15 Hydraulic Buffer - Heavy Damped

Our Heavy Damped (HD) PCC Buffer Model has stiffer hydraulic dampening and stronger return spring for high stress applications. For Pistol Caliber Carbine builds that need increased shock absorption. Can be used in typical PCC carbine builds as well as short-stroke systems, and for hotter ammo. This HD model is not recommended for short barreled builds since they do not run the bolt as hard and will get more effect from the standard model. This buffer model was developed to fill the need for stiffer shock absorption which is needed on some PCC guns. If you plan to run your gun in a short stroke manner, then we recommend this buffer with our PCC buffer weight which will add mass while shortening the stroke. Many shooters feel that this buffer with the PCC buffer weight is the softest running even with a full stroke 16" carbine.

 

Looks like the RB5015HD is available from the Blitzkrieg web site now.  Not sure if this is a beefed up version that Max has been testing or just hydraulic dampening and internal spring changes.

[MoRivera]

Yeah I have both a 5000 (regular carbine-sized) and a 5007 (PCC sized).  The 5007 has noticeably less hydraulic damping than the 5000, and when I asked Blitzkreig about it I was told it was because of the higher buffer velocity with PCC's, and the the less fluid pressure reacted more gradually or something.  I'm currently using the 5000 with a .308 Carbine spring and a wave spring in the rear of the tube.  The difference I feel between that and the 5007 and just the spring is that I get more of a jolt at the rear most travel with the longer 5007.  The wave spring, for me, cushions that hit at the rear and my dot isn't jolted as much, as well as keeping the stroke length short enough not to slam onto the bolt catch (use a Stern Defense 9mm adapter which does lock bolt open on last round).  My only concern is if I'm putting too much pressure on the 'stiffer' hydraulic chamber of the 5000 which is intended for the 5.56.  But from the looks of it with the 5015, they've gone with more pressure anyway.

 

Shot a lot of rounds so far though and it seems to be holding up fine.

[Flatland Shooter]

"If you plan to run your gun in a short stroke manner, then we recommend this buffer with our PCC buffer weight which will add mass while shortening the stroke. Many shooters feel that this buffer with the PCC buffer weight is the softest running even with a full stroke 16" carbine."

 

Checked at the Blitzkreig website and I cannot find the PCC buffer weight.  Is it a chunk of steel placed between the bolt and the buffer?  (I seem to remember reading where Max L was experimenting with this).

 

I don't know if its even important or not but how can I tell which of the Blitzkreig PCC buffers I have.  (Purchased at the 2017 Black Friday sale.)

[JsK]

Made mine, maybe they are going to have this as a production item now.

[Flatland Shooter]

37 minutes ago, JsK said:

Made mine, maybe they are going to have this as a production item now.

 

I did some back of the envelope calculations and a 1" diameter stainless steel cylinder long enough to short stroke the bolt will weigh just over 3 ounces.  Add the 6 ounces for the Blitzkreig buffer and 15.2 ounces for the bolt with the weight still in it and you have a 24+ ounce system. 

 

Sounds pretty heavy considering we felt something around 18 ounces was ideal.

 

Do these numbers come close to what you have JsK?    What are your thoughts on a heavy setup?

 

Thanks.

[HoMiE]

1” diameter steel is too big, had to have the. At stock turned down .015 to 0.985” and 1/2” thick spacer weighs approx 2oz.

 

ive tried bcg without weight and prefer them with the weight in. If you have a qc10 bolt, the buffer is almost 1oz heavier than lost standard round bar weights since the qc10 bolt weight has fingers that go along the hammer channel. 

[JsK]

As mitch said, 2oz spacer, 16oz bolt, 6 oz buffer. 

[JZELEK]

I'm curious.

With the apparent high amounts of failure with this buffer, why do most of you even bother with this product?

Is it that much better than the other more reliable systems on the market?

[CalTeacher]

43 minutes ago, JZELEK said:

I'm curious.

With the apparent high amounts of failure with this buffer, why do most of you even bother with this product?

Is it that much better than the other more reliable systems on the market?

Because it shoots considerably flatter than other buffers.  I keep a back up blitzkrieg so if one breaks I have another to use while my replacement is on the way. 

[MemphisMechanic]

49 minutes ago, JZELEK said:

I'm curious.

With the apparent high amounts of failure with this buffer, why do most of you even bother with this product?

Is it that much better than the other more reliable systems on the market?

 

It’s the flattest-shooting combination I have tried in my rifle. 

 

I run a Guard so the action isn’t direct blowback and the bolt is much lighter. I run a wave spring, then a single quarter, then a 5oz hydraulic buffer for a .308, then a Sprinco red spring.

 

Edited December 7, 2018 by MemphisMechanic