Help me understand buffer tuning

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So I built a blackout pistol and threw a h1 buffer in because I had it laying around. It seems that a lot of people run an h2. If I'm understanding correctly adding a can into the mix will cause it to cycle harsher with the h1 and the h2 would slow it back down some. Im looking at the jp silent captured spring setup but I'm wanting to swap it between a few rifles so I'm trying to make sure I understand how buffer weights work to make sure an h2 will run in the 3 guns I want to use it in:

8.3" blackout pistol gas non adjustable gas block H1 buffer
18" 223 Wylde SPR rifle gas adjustable gas block Rifle buffer
14.5" 556 carbine gas non adjustable gas block Carbine buffer

Basically I'm cheap and instead of buying multiple jp springs, I'm hoping that I can get by with swapping the same one around.
 
Can’t comment on .300bk as I’ve never had one.
I think you are going to have hard time with getting the two 556 upper to work with same buffer weight. The shorty carbine is likely gonna have a lot more gas and more violent cycle than the rifle gas 18”. Especially considering you can adjust rifle gas waaay down at the gas block.

I would consider an adjustable gas block on carbine upper of you intend to use the SCS on both.
 
I have two upper that I use same lightweight bcg and buffer system. But it is a 18” rifle, and a 14” middy (you saw this one), so they are already closer in performance, but additionally they both have adjustable gas so I can tune them to work with the same buffer/bcg.

I also have a 12.5” carbine non adjustable gas upper. For that I just drop in a different spring and an H2 buffer.

Who knows, maybe hey will all work great? You just have to try and observe where your brass is ejecting with each upper, etc.

Edit: the gas port size of your barrels will also play a roll and it may turn out they all work great.
 
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Posting in case you have not seen this.

http://jprifles.com/document_pdfs/SCS Selection Guide_690.pdf


Edit:
If you are wanting to order one soon, DSG arms have the heavy version in stock (regular is backordered) for $168 plus they have a $10 off code (10-off-150) and free shipping that ends this weekend. Shipping to NC is normally ~$7.95.

You have to sign in for the price.

https://dsgarms.com/jpscs2-15h2

According to that flow chart SBR and suppressed recommend h2 so since all of these will be ran suppressed and the blackout will be an sbr when my stamp comes back it looks like that's the way to go like I originally thought.

On the 18" rifle gas I have the option to tune gas but I honestly don't think I'll need to as the standard rifle buffer is 5oz and the h2 carbine is 4.8oz. that being said I think I'd reduce recoil by going with a standard carbine SCS (3oz) and dialing gas way down. May end up getting two SCS setups, just trying to get by with 1 for now.
 
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I found this interesting a while back, maybe it'll help.


While there is some knowledge to be had his opening remarks instantly turned me off. Combat and self defense is not the only purpose of every rifle. He seems a little "mightier than thou" by mocking people playing with buffers to reduce recoil, ect.
 
According to that flow chart SBR and suppressed recommend h2 so since all of these will be ran suppressed and the blackout will be an sbr when my stamp comes back it looks like that's the way to go like I originally thought.

On the 18" rifle gas I have the option to tune gas but I honestly don't think I'll need to as the standard rifle buffer is 5oz and the h2 carbine is 4.8oz. that being said I think I'd reduce recoil by going with a standard carbine SCS (3oz) and dialing gas way down. May end up getting two SCS setups, just trying to get by with 1 for now.

Seems like you got a pretty good handle on it!

SCS really smooths out a gun, IMO. I think you’ll like the feel. Always wanted one but I have been too cheap, lol.
 
Seems like you got a pretty good handle on it!

SCS really smooths out a gun, IMO. I think you’ll like the feel. Always wanted one but I have been too cheap, lol.

The ONLY reason I'm getting one is to get the full experience running suppressed. Seems everyone says the spring in the buffer tube becomes extremely noticable when you throw a can on. 300blk is one of the stupid quiet calibers so I'd hate to spend all this money on the pistol build and a can and skimp on the last part to make it truly quiet.
 
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The ONLY reason I'm getting one is to get the full experience running suppressed. Seems everyone says the spring in the buffer tube becomes extremely noticable when you throw a can on. 300blk is one of the stupid quiet calibers so I'd hate to spend all this money on the pistol build and a can and skimp on the last part to make it truly quiet.
Your barrel length is going to have a much higher effect on overall suppression than your buffer/spring setup in this case. I would agree on a 12" + length barrel 300BLK the spring does become noticeable but I can't help but feel like you're trying to create a problem for the solution in this case. Save your $150 imo.

Tell me if you can hear the spring in this video:

 
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Your barrel length is going to have a much higher effect on overall suppression than your buffer/spring setup in this case. I would agree on a 12" + length barrel 300BLK the spring does become noticeable but I can't help but feel like you're trying to create a problem for the solution in this case. Save your $150 imo.

Tell me if you can hear the spring in this video:



Pretty confident he's shooting supers. I plan to shoot exclusively subs, that's kind of the point of the round. I have watched a ton of vids on youtube and there are definitely some where you can here the spring. And if it comes through on video I'm certain it will be obnoxious in person with your face right over the buffer.
 
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I got to use a 18" rifle length gas suppressed at the range with and without the JP SCS (other was standard rifle buffer/spring) and the twang was very noticeable with standard buffer/spring (to me, that noise overshadowed the muzzle end noise). The SCS made it sound like a 223 bolt suppressed to me. Did not hear anything in the receiver extension. Curious how the Geissele braided buffer spring would compare as they say it takes out the twang noise too, but they do not recommend it for 300blk subsonic or rifle length extensions.

https://geissele.com/super-42-braided-wire-buffer-spring-and-buffer-combo.html
 
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I actually have a super 42 with the h1 buffer in my blackout pistol currently. I've only put a few rounds of 150 gr supers through it and it has functioned fine. But I can't speak on the spring noise as I don't have my can yet and you can't hear anything over the muzzle blast. Charging it compared to charging a standard spring and buffer is noticably different though.
 
@patina Go to 0:20 on both of these vids and play one then immediately play the other. I'm sure it's even more of a difference from the shooters perspective



 
@patina Go to 0:20 on both of these vids and play one then immediately play the other. I'm sure it's even more of a difference from the shooters perspective




I figured you were watching Leghorn's videos. If you're still wondering which version, I think you will want to go as heavy as possible for the 8.3 300blk.
 
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Based on my limited experience, I think you should run the heaviest buffer your gun will cycle reliably. Nearly all of my AR's or parts kits shipped with H1's in them. Now they all have H2's or H3's in them.

My Armalite carbine was very overgassed. I swapped it over to an H2 and now its a kitten. My pistol became a lot easier to shoot with an H2, and an H3 made a huge difference in my AR10.

I don't have any experience with suppressors, but I would assume that it would create more gas pressure in the system, and would work well with a heavier buffer.
 
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