On a Mk18 what's a good buffer spring and buffer?

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tooly Joined May 2002 Posts 12528 EE 100% (2) TX, USA	Posted: 1/29/2024 9:59:45 PM EDT It's for my son's mk18 10.3 barrel what's a good buffer spring and also a good buffer and what weight? Thanks....

TGWLDR GUN WHORE Joined Dec 2014 Posts 48744 EE 100% (446) IA, USA	Posted: 1/29/2024 10:05:27 PM EDT [#1] USGI spring and H2.
	Can't never could 'til try came along.

runguns Joined Dec 2013 Posts 955 EE 99% (76) CO, USA	Posted: 1/29/2024 10:53:52 PM EDT [#2] opinions on using the Vltor A5 system with a mk18, rc2, milspec bcg, non adjustable gb setup?

tooly Joined May 2002 Posts 12529 EE 100% (2) TX, USA	Posted: 1/29/2024 11:10:38 PM EDT [#3] Quote History Originally Posted By TGWLDR: USGI spring and H2. View Quote How ya been man?

tooly Joined May 2002 Posts 12530 EE 100% (2) TX, USA	Posted: 1/29/2024 11:13:44 PM EDT [#4] Quote History Originally Posted By runguns: opinions on using the Vltor A5 system with a mk18, rc2, milspec bcg, non adjustable gb setup? View Quote He will be running a surfire RC2. He has one. He has a BCM BCG.

tooly Joined May 2002 Posts 12531 EE 100% (2) TX, USA	Posted: 1/29/2024 11:14:32 PM EDT [#5] Quote History Originally Posted By TGWLDR: USGI spring and H2. View Quote He's running or gonna be running a surefire RC2 can.

Redoubt99 Member Joined Feb 2020 Posts 3404 EE 100% (55) ID, USA	Posted: 1/29/2024 11:24:51 PM EDT [Last Edit: Redoubt99] [#6] I have a DD Mk18 and I run it full time with a Socom RC2. USGI spring and h3 buffer.
	Dont call it a comeback, Been here for years.

TGWLDR

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Joined Dec 2014
Posts 48746
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Posted: 1/29/2024 11:28:30 PM EDT

[Last Edit: TGWLDR] [#7]

Quote History

Originally Posted By tooly:

How ya been man?

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Quote History

Originally Posted By tooly:

Originally Posted By TGWLDR:
USGI spring and H2.

How ya been man?

Copasetic

DD 10.3", correct? How old/new is his barrel?

I ask only because DD changed GP diameter a few years back. Previously 0.081" (IIRC) to 0.072" on current production.

ETA: Don't take those diameters as gospel, I'm throwing shit out from memory. Which may not be entirely accurate.

Can't never could 'til try came along.

TGWLDR GUN WHORE Joined Dec 2014 Posts 48747 EE 100% (446) IA, USA	Posted: 1/29/2024 11:35:13 PM EDT [#8] Quote History Originally Posted By tooly: He's running or gonna be running a surefire RC2 can. View Quote View All Quotes View All Quotes Quote History Originally Posted By tooly: Originally Posted By TGWLDR: USGI spring and H2. He's running or gonna be running a surefire RC2 can. Full power 5.56 exclusively, or mixed .223 / 5.56?
	Can't never could 'til try came along.

aimatdeer Member Joined Dec 2014 Posts 1749 EE 0% (0) OH, USA	Posted: 1/30/2024 12:38:08 AM EDT [Last Edit: aimatdeer] [#9] Chrome silicon spring from damage ind. H3

KILLERB6 Member Joined Jan 2002 Posts 66760 EE 100% (6) USA	Posted: 1/30/2024 2:10:02 AM EDT [#10] Quote History Originally Posted By runguns: opinions on using the Vltor A5 system with a mk18, rc2, milspec bcg, non adjustable gb setup? View Quote Don’t.
	If the truth makes you uncomfortable, don't blame the truth. Blame the lie that made you comfortable. -James Ng Uni

KILLERB6 Member Joined Jan 2002 Posts 66761 EE 100% (6) USA	Posted: 1/30/2024 2:11:05 AM EDT [#11] Quote History Originally Posted By Redoubt99: I have a DD Mk18 and I run it full time with a Socom RC2. USGI spring and h3 buffer. View Quote Same except Sprinco BLUE/H3.
	If the truth makes you uncomfortable, don't blame the truth. Blame the lie that made you comfortable. -James Ng Uni

tooly Joined May 2002 Posts 12532 EE 100% (2) TX, USA	Posted: 1/30/2024 5:17:49 AM EDT [#12] Quote History Originally Posted By Redoubt99: I have a DD Mk18 and I run it full time with a Socom RC2. USGI spring and h3 buffer. View Quote Thanks.

tooly

Joined May 2002
Posts 12533
EE 100% (2)

TX, USA

Posted: 1/30/2024 5:18:19 AM EDT

[Last Edit: tooly] [#13]

Quote History

Originally Posted By TGWLDR:

Copasetic

DD 10.3", correct? How old/new is his barrel?

I ask only because DD changed GP diameter a few years back. Previously 0.081" (IIRC) to 0.072" on current production.

ETA: Don't take those diameters as gospel, I'm throwing shit out from memory. Which may not be entirely accurate.

View Quote

Brand spanking new. 10.3 I thought they changed to 0.070"

tooly Joined May 2002 Posts 12534 EE 100% (2) TX, USA	Posted: 1/30/2024 5:19:39 AM EDT [#14] Quote History Originally Posted By TGWLDR: Full power 5.56 exclusively, or mixed .223 / 5.56? View Quote Most likely mixed. His SD ammo is speer gold dot.

TGWLDR

GUN WHORE

Joined Dec 2014
Posts 48748
EE 100% (446)

IA, USA

Posted: 1/30/2024 7:36:11 AM EDT

[Last Edit: TGWLDR] [#15]

Quote History

Originally Posted By tooly:

Brand spanking new. 10.3 I thought they changed to 0.070"

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Quote History

Originally Posted By tooly:

Originally Posted By TGWLDR:

Copasetic

DD 10.3", correct? How old/new is his barrel?

I ask only because DD changed GP diameter a few years back. Previously 0.081" (IIRC) to 0.072" on current production.

ETA: Don't take those diameters as gospel, I'm throwing shit out from memory. Which may not be entirely accurate.

Brand spanking new. 10.3 I thought they changed to 0.070"

You may be right, I've seen both reported, but you know how the web is.

Mine are Colt's/0.070" with the USGI spring/H2 they have been solid with mixed ammo unsupressed.

I didn't care for the H3 personally, too much muzzle dip when the BCG returned to battery. Quick follow up shots were difficult, IME.

As for supressed shooting, I'm still a few months out as far as wait time so I can't say one way or another yet.

Can't never could 'til try came along.

MallNinja531 Just Some Guy Joined Jan 2020 Posts 5252 EE 100% (76) OH, USA	Posted: 1/30/2024 10:07:15 AM EDT [#16] Not as saucy as a DD, but I have a "mock18" mod0 that I use a spikes ST2 buffer and standard carbine spring in. With a tool craft BCG it ran everything I put in it fine with or without a YHM TK can. I've since added a bootleg adjustment BCG to try to cut down on gas and tune it a bit, but it still runs like a swiss watch.

hoodfu

Joined Sep 2009
Posts 2275
EE 0% (0)

USA

Posted: 1/30/2024 10:12:36 AM EDT

[#17]

Quote History

Originally Posted By MallNinja531:
Not as saucy as a DD, but I have a "mock18" mod0 that I use a spikes ST2 buffer and standard carbine spring in. With a tool craft BCG it ran everything I put in it fine with or without a YHM TK can. I've since added a bootleg adjustment BCG to try to cut down on gas and tune it a bit, but it still runs like a swiss watch.

View Quote

I went the bootleg option and it definitely worked. By diverting all that gas to my face instead. It's pretty much lung cancer to shoot my mk18 with an rc2.

HipSh0T Crazy for Retro Rifles! Joined Sep 2008 Posts 7971 EE 100% (236) NH, USA	Posted: 1/30/2024 12:07:44 PM EDT [#18] Colt spring and H2 is hard to beat
	WTB : KAC FF M4 RAS P/N 20208

mak0 Joined May 2007 Posts 15818 EE 100% (56) PA, USA	Posted: 1/30/2024 12:11:49 PM EDT [#19] I run a standard milspec spring and H2 buffer. With the suppressor I get ejection around 3:00 position.

MallNinja531 Just Some Guy Joined Jan 2020 Posts 5257 EE 100% (76) OH, USA	Posted: 1/30/2024 6:46:56 PM EDT [#20] Quote History Originally Posted By hoodfu: I went the bootleg option and it definitely worked. By diverting all that gas to my face instead. It's pretty much lung cancer to shoot my mk18 with an rc2. View Quote Interesting. That combined with a homebrew gas buster made it manageable for me. Not great, but not like getting pepper sprayed any more.

hoodfu

Joined Sep 2009
Posts 2276
EE 0% (0)

USA

Posted: 1/30/2024 7:10:52 PM EDT

[#21]

Quote History

Originally Posted By MallNinja531:

Interesting. That combined with a homebrew gas buster made it manageable for me. Not great, but not like getting pepper sprayed any more.

View Quote

I took video from the side of me shooting it and my radian sd handle is doing a reasonable enough job, but a giant toxic cloud is coming out of the ejection port. I've got an adjustable gas block on a 5.56 upper machine gun and even suppressed its no problem because I can adjust it way down. Makes me not want to put anymore money into the mk18 for like the rc3 or something because there's newer better solutions out of the box these days.

TBone556 Joined Dec 2015 Posts 2185 EE 100% (5) TX, USA	Posted: 2/7/2024 2:33:46 AM EDT [#22] I’m a big fan of the VLTOR A5 and its copies and that’s what I use going forward. The bcm version with the T2/H2 works well with a DD 10.3, it’s smoother. I will say with a 14.5 and 16 using the VLTOR tube and a JP polished rifle spring with a H2 VLTOR weight is insanely smooth.

JoeDevola Joined Sep 2020 Posts 2347 EE 100% (37) USA	Posted: 2/8/2024 10:36:28 PM EDT [#23] Quote History Originally Posted By TGWLDR: USGI spring and H2. View Quote That's exactly right.

On a Mk18 what's a good buffer spring and buffer?

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