The HAC-7 was a rifle designed in the 1980s, and only available for a short time before the Holloway Arms Company went out of business. It was designed as a military-style weapon, although what military contracts it may have hoped for I don’t know. The design concept was quite good, utilizing elements form the AR, AK, and FAL rifles (mostly the AK). It was chambered for the 7.62mm NATO cartridge, using aluminum waffle-stamped AR10 magazines modified with a notch in the spine for the HAC-7’s AK-style magazine catch.
Originally, plans were to offer the HAC-7 in a variety of configurations – left and right handed ejection, normal, carbine, and sniper barrels, full-auto versions, etc. The financial failure of the company prevented this from happening, though. In total, approximately 300 guns were made, including about 30 left-handed carbines, about 20 left-handed rifles, and a single sniper model. Twelve were set aside for manufacture as full-autos, but they were later assembled and sold as standard semi-auto versions instead. All the guns were equipped with side-folding stocks.
Thanks to a generous reader, we were able to borrow a HAC-7 for disassembly and some range testing, and put together a video on it:
So it’s effectively an ‘AK-ified’ M16? I’m surprised there don’t seem to be more ‘best-bits’ guns out there, but I suppose you run into patent issues if you get too enthusiastic.
Also I can see why it would have problems selling, it’s a brilliant design but doesn’t seem to add much new.The design seems simple and reliable (with some tweaking needed as mentioned in vid), but not simple enough to compete. The main market would I imagine would be a country looking a for a relatively cheap, mechanically reliable gun, which the AK already quite happily fills.
Another vote for ‘best bits’ new feature. Good idea Nick.
Any patent issues for an AK / AR hybrid would have expired long ago, though.
There was an interesting 7.62*51 rifle developed in the Dominican Republic along “best bits” lines.
It used a gas piston copied from the Us M14, located under the barrel and a tilting bolt copied from a FAL. (They could have used the over barrel gas system from a FAL and the turning bolt of an M14, and still come up with a good rifle)
My old copy of Jane’s Infantry Weapons has all of two lines of text and a single photo showing mostly the underside of the gun.
apparently it was called the “Model 62” and not many were made…
Wasn’t it Király’s Cristóbal Modelo 3?
I couldn’t get the jpeg to show, but guessing it is the same one, Manowar shows the same photograph as Hogg/Jane’s as the Cristobal Model 3, and a .30 carbine as the Mod 62
Similar in concept to the Daewoo K1 and the AR 18 – both of which bortrowed heavily from the FN-FAL & AK systems; the gas adjustment/cutoff is a virtual ripoff of the FAL…First I’ve seen or heard of thjis rifle – Thanx to all concerned.
CB in FL…the cutoff closely resembles my late, lamented Argie FAL
I really like the added attention spent to reduce the amount of moving mass in the piston. The one element I didn’t see you mention was the barrel attachment system. Did he manage to incorporate any kind of quick change feature (besides just swapping the entire upper receiver), or was it a standard press fit affair such as an AK or FAL system?
Fal’s barrels are not press fit but screwed. Since it’s a .308 mag fed rifle, quick change barrel system is useless.
no quick change barrel. in fact it is difficulate to get the barrel out.
For those interested, here’s a couple helpful links on the HAC7 platform:
Great rifle and designer. Robert Holloway deserves more credit to his excellent design.
I’m not sure the gas tube / piston arrangement was for weight as you described. What the gas tube section does is increase dwell time of the system where a true AK copy would have the bolt group moving back sooner. This is speculation though and you might be correct.
I expect someone to come up with a clue regarding this point; you seem to be the first. I think you are right, this is not about reducing the weight. The way I see it is that the gas tube volume on its own (in DG system) will not change much (such as in AR15 where rate of fire is at around 830 RPM). In most ‘regular’ cases, when the space between face of piston and bottom of gas compartment is small, the response is immediate. In case such as we have, the gas has to ‘pack the space’ which is larger (occupied by ambient pressure) to get combined bolt&piston assembly moving. This will take some time, therefore here is the built-in dwell. Does anyone have an alternate interpretation?
If you watch a slow motion of an AK firing, the thrust from the front of the gas cylinder acts on the gas block, and you can actually see the barrel bending.
The whipping about of the muzzle which results, will increase shot to shot dispersion.
The AK design further exacerbates this with its impingement type gas system (as opposed to an M14 cut-off system) and with the length of the gas block giving more leverage.
one of the advantages of the small tube, is that it will (to an extent) limit the ammount of gas thrust placed on the gas block – and hence limit that source of barrel whip.
I’m guessing that the gas cylinder itself must be anchored in the receiver.
There probably are advantages to be gained from the flow resistance provided by the small bore tube.
with respect to weight reduction of the piston, bolt carrier and bolt assembly,
The AK is notable for the very heavy bolt carrier compared to its bolt, and this is probably one of the factors contributing to the AKs functional reliability.
the down sides include the higher inertia for getting the thing moving (the equal but opposit rection to that is taken by the gas block and results in the barrel bending.
and the higher inertia to get the thing stopped and moving forward again.
For a given weight of rifle, the more weight you allow in the moving parts, the less you can assign to the receiver, stock, barrel etc
hence a thin, bendy barrel, and less weight to damp out the slap as the moving parts hit the back of the receiver (you get more of it on your shoulder).
certainly the HACs bolt carrier assembly gives the impression of being lighter than a comparable AK’s
I’m guessing that this was done to allow more weight to be put into other parts of the gun, possibly partly in the search for softer recoil characteristics.
another factor with a shorter gas piston rod is rod stiffnes. One of the wear factors is flexing of the piston rod causing the piston to scrape in the cylinder.
On the AR18, this was addressed by a ball and socket joint at the back of the piston (I’ll try to look the patent ref out)
The HAC appears to have both a joint allowing the piston some play – and a shorter and therefore (assuming equal cross section) stiffer piston rod than an AK
The HAC’s gas system is going to complicate dis assembly compared to an AK, but with 7.62*51, the chances of meeting corrosive priming was extremely small, and I think that the compromise is a good one.
These are valid observations. Just as extension of your thought, I am going to elaborate on how light the moving parts can be; of course the lighter the better, within strength limit.
Forces back – unlock, extract, eject – are supplied by piston, forces forward by spring(s). All what is needed is to have enough to strip round, chamber it and lock. and conversely, only that much is needed to push whole assembly back.
Yes, there are practical considerations, which drive most of it and – surplus for dirty gun. So, let’s assume that this fellow came close to optimum (and really, for .308 the action is skimpy). The gas tap adjustability is also a plus. I like those light parts (and he did additional relief).
But still, why that straight gas line portion? Only thing coming out of it may be the delay. Only he could tell us for sure.
“the moving parts can be; of course the lighter the better” – Actually, no. The inertia of the moving mass is what makes the rifle function after the initial gas impulse.
If the inertia is too low, the rifle will be unreliable because it won’t be able to overcome a bit of minor dirt or resistance. If the inertia is too high, the gun will be very “lively” when the bolt group hits the ends of travel in the receiver. There’s a certain optimum mass that balances these two problems.
This is why a rifle that works great for recreational shooting on the range may not be a good design for military purposes. In one case you want a “nice shooter” that is as accurate as possible. In the other case you want something that is guaranteed to work under all circumstances. There are different needs for different applications, and military needs are very different from those of recreational shooting.
Yes MG, I am aware of these ‘details’; I believe did not omit them in my note. Actually, to move things (bolt&such) forward you have springs; mass is kind of no use on the way forward. Now, let’s admit it – the reciprocating mechanism is really silly devise; there is very little (part of mentioned mass) you can do with it. If it was possible to connect it to a crank, such as on horizontal shaping machine….., but where to get space for it?!
IIRC Robinson had some machinegun patents along those lines
Thinking about gun mechanisms which try to practice aikido with recoil
There’s the BSA “Ralock” .22 gallery rifle.
Think of a semi auto Remmington Rolling-block that fires from an open bolt and has a built in case catcher for the empties
Hi, Keith :
That is a really fascinating and interesting patent — thanks so much for sharing it. To your knowledge, was this patent eventually incorporated into a production gun?
BSA produced the Ralock commercially. I’ve never knowingly seen one in the flesh, but I’m keeping my eyes open whenever I’m in a gun shop.
The open bolt guns blog has some photos of a Ralock dis assembled. Click on them as there is quite a lot of cropping to fit them on the blog page – you get a lot more when they’re clicked.
It’s a really interesting blog and well worth a look around – unfortunately it had largely exhausted its field and gone dormant before I discovered it.
I really like open bolt .22 actions, there’s no messing about with ejecting and usually loosing a chambered round to make the rifle safe, just drop the mag and put the bolt forward, and with most open bolt rifles, there’s never any question about whether it’s cocked.
Thanks for the additional information , Keith, and for taking the time to answer my query! I’ll definitely be looking more closely at the website you recommended. Cheers!
Judging from the photographs, Chris Brosnahan has a good point about the gas regulator ( cut-off ).
Did some reading up on it, seems the inventor thought he could sell it to the Texas Nat’l Guard. One web post claimed that the CNC machined reciever was too expensive, so investment castings were tried and failed and at that point the money ran out. Even if it had been fine tuned, if it cost too much to build it wasn’t going anywhere. This was also back when CNC equipment and software was not nearly as affordable as it is now.
Might be a case of a really good design function-wise, but not really well designed for manufacturability. The grease gun and the AR-18 are two examples designed for manufacturability. I think Bill Ruger’s designs were successful not due to ergonomics or function but because he designed them to be manufactured, creating new manufacturing methods when needed. All that said, if someone can finish the design and produce it, sign me up.
Looks to me like stamped sheet metal.
Look at the video where the trigger group is examined. That receiver is machined. Could have been machined from a forging, a casting, or bar stock. Web posts claim it was machined from bar stock, which makes sense given the scale of production. Problem with bar stock is it takes longer to machine and a big chunk of the material cost ends up in a bin of metal chips.
A couple of different web posts also claim to be from people who saw the CNC machines running in the factory. CNC these days might make a go of it. CNC in the mid-eighties was what? Paper tape or cassette tapes, maybe direct control by a VAX? It is night and day compared to CNC today–functionality and cost.
My impression is that you spoke of upper (or action housing). The bottom portion is definitely machined from bar; yes lots of chugging too. In early eighties, it was done already by CNC (software programmed). We had Hitachi-Seiki machines.
Not that different when compared with FNC:
The FNC commenced to be fielded in around 1980 as well.
One must wonder though why 7.62mm; in 1980s, the 5.56mm was firmly in place. It would be hard to convince brass’ mindset of something else. So, the timing is in question.
But the truth remains that the gas system – half direct/ half piston with full adjustability is unique and beneficial for purpose of this concept. It looks really well thought out. My thumb’s up!
he was trying to sell it to the texas national guard and private security companies nuff said
Bob Holloway was firmly in the “5.56 is a poodle-shooting varmint round; Real Men use 7.62x51mm!” camp.
i wonder if mr. Holloway is still around
Robert Holloway is living quite comfortably in the Pacific Northwest. He’s working for a major oil company and travels the world. On the side, he still dabbles in gun design. I think someday we’ll see Bob’s name pop-up in the gun industry again.
I certainly hope so. An innovative mind like that is not to be wasted.
That’s good to know that he is still alive and kicking.
So an interview about the company and/or his interesting gun design is still possible
Thanks for posting this review.
A friend of mine had one in his gun shop back in 85 or86 we shot it at the range the inventor tried to sell it to the Texas state guard not the national guard
Interesting — As an actual user, what were your general impressions of the HAC-7?
Gee thanks Ian. Now I want one. Great review.
“Twelve were set aside for manufacture as full-autos, but they were later assembled and sold as standard semi-auto versions instead.”
Were those 12 registered as machine guns before being assembled?
Patent Holloway HAC-7
BTW, I went back to look at Howa89 – very similar gas tap arrangement. That seem to support thesis on “gas dwell” function.
This appears to be a slick solution, although ease of cleaning might be an issue.
I recall the Holloway being promoted in Soldier of Fortune around 1985. One of the writers there (Chuck Taylor? Ken Hackathorn?) was quite taken with it. There was rather a lot of bias against the “poodle shooter” 5.56 at the time.
As was usual in weapons reviews of the period, and today, stoppages were never mentioned.
The A-10 mags stayed very common and cheap (after all, who had an AR-10?) until Knight introduced the SR-25. Reed or one of his guys cagily bought up the mother lode of the things, and they were modified to work in the SR’s more AR-15-like magwell (the original AR-10 had a side mag release, but no bulged section of the mag). A couple years ago I had to hunt 7 up for a semi AR and I think they averaged $60 or so. But I was still getting new ones in wrap from Artillerie Inrichtigen. Like the G3 alloy mags, they were meant to be disposable and manufactured in staggering quantities (PTR Industries has a stock of some 200k G3 mags, still in the wraps from the German contractors, mostly Rheinmettal).
The trigger and disconnector of the AK, like that of the AR, seems to borrow from the M1 Garand. I’m not sure where Garand lifted it, but maybe the Remington Model 8 or the Browning A5 — which brings it back to JMB Himself.
I owned one of these 20+ years ago. Serial number 282 or 283 I think. I bought it new for around $500 when the FAL was more like $800. Mine worked fine as long as the mag’s feed lips were undamaged and the gas was set right. Those feed lips were easy to bend out of shape as there was no support at the back edge of the magazine like current AR or FN mags.
The general feel of the thing was more of a pre-production gun. Lots of sharp corners. Roll pins were used almost exclusively and I ended up making a few from drill shanks. The extractor pin was one of those.
The buttstock was terrible. The shoulder plate was flat and had nothing for grip, so it would slide off your shoulder in a hurry. the light gage tube frame of the buttstock was made of aluminum (I think) and pinned to the socket / hinge assembly with a roll pin that was way too small. That loosened up badly after 2-300 rounds. The hinge was copied from the FN PARA and was good. I ended up building a wood stock that replaced the whole folding assembly.
Almost all of the corners on the receiver (upper and lower) were left square, nothing was rounded off. It was deburred, but those square corners were a bit harsh.
The pistol grip and handguard were very comfortable.
The gas system was easy to clean and adjust.
The sights were very similar to the M16A2 in appearance.
The rifle came with 2 mags and a serial numbered belt buckle.
I hope that helps,
Great information from one of the few HAC-7 owners I have come across — thanks very much. BTW, do you still have the gun? It must be a pretty rare collector’s item by now.
I personally have two (one carbine and one rifle) HACs and I love them both. Of all the .308s I own, the HAC is one of the smoothest shooting rifles I own. I do agree will Scott on all the faults the rifle presents. Oh how I wish someone would bring back an Enhanced HAC7 (EHac) to the commercial market. Hint hint hint….
Lol, my name isn’t “Eskimo”, it’s ESK. Damn AutoCorrect…..
Oh one other thing.
When I mounted a scope on it (receiver was drilled and tapped from new) you couldn’t use the charging handle. The reason was that your fingers would hit the scope rings/ mount. That I fixed with the bottom of a 12gram CO2 cylinder. I cut the bottom 3/4inch off of a cylinder, drilled a hole in the center and put the screw that held the standard cocking handle thru. I didn’t remove the standard handle, just added to it.
I agree on the charging handle. I always though that Holloway should have made a detented folding handle that folded out to the 9 o’clock position, for easier access around the scope. Hey, what do you expect from a weapon platform that roughly got to 400 units..
No, I traded for 3 other guns. A Colt 1991A1 commander size for the then girlfriend, now Missus. A No. 5 Jungle Carbine. And something important that I can’t remember what it is.
I later finally did get a FN and if I had it to do over I would have bought the FN over the HAC7. I don’t know about the HK 91 as I’ve never shot one.
I own a HAC-7 Standard Left Handed. It was still in the box never been shot. Has the belt buckle and the manual. This thing is sexy.
Jollycory, If you haven’t done it yet, please registry your serial number on http://www.hollowayarms.com. Thanks!
Is there a place to see what these rifles current value?