SP5 Modifications for SBR?

[whifflinggoose]

Yes. Send me an email/PM.

Hello, I'd like to do the same. I do have a 3D printer so I would only need the stl file. I am a new member (I signed up to PM you) but I am unable to send you a PM for some reason. Please contact me if you can. Thanks.

 

[wreckdiver]

Even with the new brace/ sbr BS I still want to sbr an Ap5. Trying to figure out the best way to stay legal and hit the magic “29”. Is the a2 stock with 3D printer mod the best way to achieve this?

 

[teratos]

What length barrel is on these?

 

[wreckdiver]

I think the barrels is 8.9”. With a standard hk a2 stock it’s about 27”.

 

[teratos]

I think the barrels is 8.9”. With a standard hk a2 stock it’s about 27”.

Thank you.

 

[smdub]

What length barrel is on these?

Dr, if you're thinking about SBRing one of these I have another clever idea. Waiting on backorder parts from Brownells...

 

[wreckdiver]

Do tell.

 

[Mike OTDP]

I've got the same problem. Current thinking is to take a telescoping arm brace (which I have), cut the rods about an inch from the brace. Then fit an extension to each rod (probably a piece of steel tubing) and epoxy it in place.

 

[teratos]

Dr, if you're thinking about SBRing one of these I have another clever idea. Waiting on backorder parts from Brownells...

I am. I shared my idea for a reflex suppressor with you a while back. I gotta see how long the SD fore end is. I may buy a longer barrel and cut it long enough to make 29”.

 

[namelessname120]

Hopefully with this stock,it should make it to Maryland length give or take a half an inch. They have 2 different lengths for the stock . The 11 inch along with the 1913 adapter should help.

SKELESTOCKS

The A3 Tactical Skelestocks are fixed length skeleton stocks machined completely from 6061 aluminum. They are available in two lengths: 9.50" and 11.00".

a3tactical.com

 

[ST19AG_WGreymon]

I found a solution. It's expensive though.

I got a F5MFG stock:

F5 MFG Modular Stock System (MSS) For MP5 and Variants

Shop F5 MFG Modular Stock System (MSS) For MP5 and Variants and other firearm products and accessories with exclusive online offers only at F5 MFG.

f5mfg.com

In its OEM form it will bring the OAL to 27.26". However there is more adjustment length to the stock, you just need to remove the retention screw on the bottom and it'll net you a little under 29" in adjustment. I cut a little more material away from the last locking "square" with a Dremel to get to 29".

Before:

After (ignore the screw at the end, I was experimenting):

You have keep the retention screw removed in order to reach full extension. This also means you can pull off the lower portion at any time. This is a non-issue as you can just keep it at the preferred length anyway.

The only issue I see is that the iron sights become unusable so you will need a red dot mounted. You also need to transfer your buffer pad from your brace.

 

[ryu.sutakusu]

Paging Mr SG. Paging Mr SG...

Pm sent

 

[Sgt6402]

There is this option, have this barrel installed. You can still get 29" with an A3 stock.

RCM HK 34 STYLE 9MM MP5 BARREL 12.700 LONG - Rim Country Manufacturing

These 9MM barrels are made from Mil-Spec 41V50 CHF blanks. Expertly profiled & chambered in the desirable 16 flute chamber profile. Each barrel is then finished with the ultra desirable “nitrided” process for ultra long life and the finest in corrosion resistance. This barrel is the first...

rimcountrymfg.com

 

[smdub]

There is this option, have this barrel installed. You can still get 29" with an A3 stock.

RCM HK 34 STYLE 9MM MP5 BARREL 12.700 LONG - Rim Country Manufacturing

These 9MM barrels are made from Mil-Spec 41V50 CHF blanks. Expertly profiled & chambered in the desirable 16 flute chamber profile. Each barrel is then finished with the ultra desirable “nitrided” process for ultra long life and the finest in corrosion resistance. This barrel is the first...

rimcountrymfg.com

MP5 -> HK34K. (that 12" bbl)
Press out old bbl (have to remove the cross pin)
Cut off old cocking tube
Source and weld on new longer cocking tube
Press out pin and then press triple frame off
Press in new bbl (and get it to headspace)
Machine new cross pin hole (likely need oversized pin since you'll egg out the trunnion slightly)
Press triple frame onto new bbl
Source new 53 bolt carrier and cocking extension
Source new 53K length handguard (might have to trim down the mag end)
You might need a different locking pc.
Refinish
All in you're easily looking at $600+ for just the parts. Labor will more than double that.

All of that is required because that 12" bbl doesn't have the boss in the right location to keep to front sight triple frame in the correct place. Its designed for a different, longer gun.

 

[Sgt6402]

Might be worth it to someone to have an SBR Mp5 clone with an A3 stock to go this route instead of some abomination chopped up stock of some sort.

There are those that $$$ is not an issue so now they have another option and there are some pretty talented HK Smith's out there.

Does not matter to me either way.............. just an option for someone if they want it bad enough

 

[smdub]

Would be cheaper just to sell what you have and go buy the right gun. Several builders offer HK34K versions.

Can get a telescoping stock to work fine. Somewhat like what I offered for the MPX. If Brownells would get some darn magpul stocks in and ship me the ones I ordered, I could modify those easily.

 

[Ghostrider1]

Choate sells extra spacers for this, so theoretically one could just add spacers until the proper length is met, right?

H&K 93/94/MP5 Adjustable Length Side Fold Stock – Choate Machine & Tool – Choate Store Home

 

[smdub]

Yes. But you end up w/ a very long LOP. A folder is also one 'evil feature' - so no flash hider or suppressor.
The advantage of a telescoping stock is you can still adjust it to the desired LOP even with the spacers and its not an 'evil feature'.

 

[outrider58]

Yes. But you end up w/ a very long LOP. A folder is also one 'evil feature' - so no flash hider or suppressor.
The advantage of a telescoping stock is you can still adjust it to the desired LOP even with the spacers and its not an 'evil feature'.

3 lug adapter...

 

[ST19AG_WGreymon]

I would just pin the F5Mfg stock so it doesn't fold and you'll have a great collapsible stock that you can collapse to A2 length.