Received an email from Todd @ ORF today
The AK Files Forums - OhioRapidfire is NOT COMING THROUGH
Anyone know how old he is? 25-30? I have never met him
Us Army (Ret) INFANTRY.
I AM MY COUNTRY'S STRENGTH
Nope. No applications here are being approved. They're being real sticklers about that. I've read so many horror stories about customers not being satisfied, that I don't even want the responsibility (post 197)
I received a tracking # from ORF and it's being returned, unrepaired. They claimed in their emails that they've rewelded the broken cocking tube. We'll see.
In my year and a half wait, I've since acquired a TIG & mill, and may try tackling it myself. Used a MIG (w/ no gas!) to build my 51 & 51K so I may be able to pull it off - maybe. It will be my first HK beltfed build experience, but I have the Vollmer '21 here, to study, and that will help
Rifle arrived and works purrfect
Last edited by cntrailrider; 03-30-2009 at 03:41 AM.
Good to hear all is well. I was worried for you and Todd. It is no fun to see people get screwed.
Glade to hear that you got your rifle back and it works. Too bad you had to resort to what you posted to get satisfaction. One favor to ask, could you post some pictures of the H&K beltfeed system and how it works on a 91 please.
Thanks Guys -
I'm so glad that ordeal is over, and had a happy ending. They really do possess the knowledge and ablilites to build great stuff
The BF mech on the '91 is the same as a '21, with the only difference being the fixed barrel instead of quick-change. Unfortunately those units have skyrocketed in price IF YOU CAN FIND ONE!
Here's the '21. The BF "box" is the same in both
You press a button to unlock the mechanism, and it slides out
That little tit on the upper right is the feed lug, which engages the BC. The diagonal cam slot in the BC slides it side to side on the shaft. Very limited side-to-side travel, for producing all that pull on the belt. All the pull is accomplished on the back stroke (ratchet style). The 21E's are set up differently, and apparently use the fore AND aft stroke of the BC to operate the feed mech. I've never studied one. They are considered the Cadillacs of HK beltfeds, and the price tag reflects that too. Lots of excellent pictures (prices listed) on this link: HK Parts | HK21 HK21E HK23E
Sorry its so dirty. Flash makes it look worse than it is
The upper & lower plates inside the feed box are easily removable w/o tools, in seconds. You can see how critical the placement of the feed box is
One thing I don't like about these is you can't pull empty links through, without great difficulty. So the first link in needs to be loaded (unless I'm missing something) They use German DM1 links, but backwards. I have starter tabs on both ends of every belt. Only $3 each from Robert. One end is for the MG47's / 7.62x39 going one way. The other end is for .308, going the other direction in HK's. I guess if you go far enough (meaning you've spent everything and are broke) things begin to come full circle lol
Thanks for the pictures Steve. That's kind of how I figured it to look like. Could I ask you one more thing? What does the ratchet mechanism look like? And thanks for the compliment on the BP. The mistake I made on it was I built it on a standard thickness ES receiver except slightly shorter so it is way to heavy. I need to mill some lightening cuts into it and perhaps mill the internial corner angles away between the cap screws.
Just snapped these pics of the BF Mech, but am not going to disassemble the ratchet assy. Did that once and it took the rest of the day to get it back together. Everything is close-tolerance machined and a bit complex. I don't know the real names of these parts, so bear with me. I spoke with Ralph @ RDTS who is The Recognized Expert on HK beltfeds, and even he uses layman's terms like 'that tiny tab thing in there...' I'd like to have an exploded parts diagram, in English
The 'rachet teeth' are in the middle black section beneath the large snap ring. The black plastic piece is a dust cover
The feed stud slides on the shaft. The 'car' it slides on, has a lever/ear which engages the cogs. It only engages when moving INWARD (to the right, as pictured). It has a STRONG return spring
Close-up of the shaft it slides on. Full travel is only 1/2"
The floor of the feed tray, and feed sprockets which push the belt/links up towards the feed slot on top (more about that, below)
Looking edge on; tension arm with a roller, which keeps the belt firmly in the feed sprocket teeth. It's loaded with a torsion spring. Length of up-travel determines how strongly your belt is held. The sprockets are on the same shaft as the ratchet cogs
The tension arm. How high it travels is critical. At first, mine was too tight for a belt to even be pulled in. I bent it up almost perpindicular to the floor (to lengthen the stop & increase clearance for the belt) then put a section of roll pin on the ear to open it up even more. Those ears are known to break then you're screwed
Here's the upper feed tray (or plate) with a spring-loaded cartridge guide. Single unit. The small square thing on the VERY BOTTOM is a spring-loaded thumb latch which locks it into position in the feed box
Installed in the gun. The feed box holds the 3 components in the correct position, so they work together. Look at post # 207 above; pics 3, 4, 7 & 8
Ah yes the 3rd component, unmentioned till now. It's the plate which goes in the bottom of the feed box (two gooved tits latch it into place) with tracks, so the feed mech can slide in/out for easy assy
All the pieces are made from sheet metal stampings which are hardened. Super-compact design, cheap & fast to produce IF you have the tooling to make the stampings. Whoever engineered this was a genius
As far as I know, individual replacement parts for the BF mech aren't sold. If something goes wrong, the whole unit is replaced at a cost of $2K+. Now you know why I don't want to take it apart!
Thanks a lot Steve for the extra pictures. Know I understand how it works. Very clever those Germans! I don't think I would take it apart either. I can see enough from your pictures to see what your describing. I might try making one for my FAL beltfeed