[wdritchey]

MR A1 with a 10" (ish) barrel vs a MR A4 with a 10" (ish) barrel.

MR762A1 vs A4 are very close, but the MR556A1 v A4 is going be be a hug difference. A big part of this is the barrel which is weight up front where you want it least. The other is the handguard being significantly lighter. You can look up the numbers, but it's significant weight savings.

 

[DontTreadOnMe]

I was hoping to avoid GB and nearly bought the pistol listed by UNIGUN but seeing that they charge an in-store fee to pick up weapons purchased at their store has me looking elsewhere.

Headsup…Texas gunstore shows to have in stock. Buy HK MR556 A4 Pistol online - Texas Gun Store

 

[wdritchey]

View attachment 452918
I swapped a few components (nothing invasive) on my 762A4. Hopefully this answers some questions regarding the G28 stock and Geissele hand guard compatibility. I will say the N/S switch appears very tight in the channel of the Geissele HG. I will be reassessing this week, in better lighting, to confirm it clears although I felt no resistance while installing the rail.
I’ll be putting on a HUXWRX muzzle device this week, NF ATACR 4-16x42, and a bipod with hopes of getting it to the range next weekend.

Cheers

Please report back. I have the same handguard that I was hoping to use on a MR762A4. I'm also kind of loving the mix of black, FDE, and RAL8000 which I didn't expect would look this good. I'm tempted to copy you haha. I have a black G28 stock that I may or may not put on. Love the look of it, but undecided if I'll actually need the additional height or if that will in fact worsen the eye relief. Won't know until I start putting things together.

 

[NoHo Hank]

Headsup…Texas gunstore shows to have in stock. Buy HK MR556 A4 Pistol online - Texas Gun Store

Thanks man! I will reach out to them first thing tomorrow AM to confirm stock. Despite their site saying if it's in stock, it's available, I was able to add 140 of these pistols to my cart. So not sure if stock is legit or not.

 

[dragnet]

Just found out the Geissele MR762 trigger doesn’t work with the new A4 45 degree safety, unfortunately. The stock trigger isn‘t bad but it’s heavier and has more creep for sure.

 

[UMP45 ENTRY]

Just found out the Geissele MR762 trigger doesn’t work with the new A4 45 degree safety, unfortunately. The stock trigger isn‘t bad but it’s heavier and has more creep for sure.

Same for the MR556A4, just have to grind a tiny bit off. Takes 2 minutes. Other option is to order the @HAUS TOOL 45° axle. The Haus one has no issue.

FIRE CONTROL AXLE HK MR95 HAUS - HAUS MANUFACTURING LLC

Short throw fire control axle for the HK MR95, MR556 A4, MR 762 A4, MR308 A4, HK416 A7 and HK416 A8 rifles

haustool.com

 

[dragnet]

Same for the MR556A4, just have to grind a tiny bit off. Takes 2 minutes. Other option is to order the @HAUS TOOL 45° axle. The Haus one has no issue.

I think I'll pick up the HAUS one, for some reason the HK safety axle's safety detent pockets are milled out wider so there's some slop laterally which I don't like the feel of.

 

[dragnet]

Please report back. I have the same handguard that I was hoping to use on a MR762A4.

I have the same rail and can take a look too. It’s hard to get a good look in there with a phone cam but it’s definitely super tight in there. There is clearance and nothing touches when installing but there is barely a gap. Perhaps he can get better pics than I can.

The rail measures 17.6mm wide in that section, and it gets scalloped out slightly at the end near the gas block. Can’t get calipers in there but maybe a hair over 18mm. The gas block itself is about 16-16.1mm wide. This means where the gas block is you have maybe 1mm to either side, or slightly less.

 

[apocalypserisin]

Would the 762a4 gas block fit on an old heavy profile barrel?

 

[nightscape]

Headsup…Texas gunstore shows to have in stock. Buy HK MR556 A4 Pistol online - Texas Gun Store

scam website

 

[tlrgsxr]

Where do i have the best shot at picking up a MR556A4 pistol? Sadly I missed out on the batch that Rooftop had a few weeks ago.

Refresh this page whenever you happen to be on the internet. I’ve seen them at 4-5 places in the last 2 weeks (got one too).

https://gun.deals/search/apachesolr_search/642230269439

 

[wdritchey]

Would the 762a4 gas block fit on an old heavy profile barrel?

They will not. I asked HK this before deciding to sell my A1 and buy a A4.

 

[JJS1313]

Please report back. I have the same handguard that I was hoping to use on a MR762A4. I'm also kind of loving the mix of black, FDE, and RAL8000 which I didn't expect would look this good. I'm tempted to copy you haha. I have a black G28 stock that I may or may not put on. Love the look of it, but undecided if I'll actually need the additional height or if that will in fact worsen the eye relief. Won't know until I start putting things together.

As dragnet found, getting quality pictures with a phone is no easy task. Here is the clearest picture I could get, hopefully you can zoom in.

 

[wdritchey]

As dragnet found, getting quality pictures with a phone is no easy task. Here is the clearest picture I could get, hopefully you can zoom in. View attachment 453092

I know the factory handguard is cut out to easily adjust the gas block. Can you still adjust it with the geisele rail on there?

 

[JJS1313]

I have the same rail and can take a look too. It’s hard to get a good look in there with a phone cam but it’s definitely super tight in there. There is clearance and nothing touches when installing but there is barely a gap. Perhaps he can get better pics than I can.

The rail measures 17.6mm wide in that section, and it gets scalloped out slightly at the end near the gas block. Can’t get calipers in there but maybe a hair over 18mm. The gas block itself is about 16-16.1mm wide. This means where the gas block is you have maybe 1mm to either side, or slightly less.

View attachment 452990
View attachment 452989
View attachment 452988

Though the gas block and switch are shadowed out in this pic, you can see daylight in between the switch and rail, reaffirming there is no contact

 

[JJS1313]

I know the factory handguard is cut out to easily adjust the gas block. Can you still adjust it with the geisele rail on there?

Negative. Geissele rail has to come off to switch between N/S

 

[JJS1313]

Side by side comparison between the Geissele 417 and the factory MR762A4 handguards.

 

[wdritchey]

Very interesting. I wonder if Geisele will offer an updated model with a cutout to adjust the gas block. Good to know either way that it’ll fit and clear.

 

[TaTaTyrone15]

Just picked up the MR762A4. Saw some posts that it may be an in between profile between the new LT barrels and the old heavy ones, but it looks the same as the current MR762 profiles. Here’s the A4 next to the old heavy, seems almost anorexic still in comparison!

Measures 19mm before the gas block, 17mm after.

Interesting, the new gas block only utilizes one roll pin.. Wonder if the new adjustable gas block will be sold as an individual part on HKusa's shop. Could use one on my MR762A1..

 

[wdritchey]

Interesting, the new gas block only utilizes one roll pin.. Wonder if the new adjustable gas block will be sold as an individual part on HKusa's shop. Could use one on my MR762A1..

It will be available, but it will not fit. I reached out to HK cs and asked this, because I wanted to do the same.