by Clint McKee
Clint, tell us about the Chinese M14S
I'd be happy to go through this. Here's the scoop:
1. The locking lug helix (surface contour) of the Chinese bolt does not agree/match the locking lug helix of the receiver. Thus, the bolt locking lug surfaces only partially contact the receiver locking lug surfaces. As you fire the rifle, the bolt will "collapse" back onto the locking lugs of the receiver until "enough" surface contact is engaged to stop the rearward force caused by the 50,000 PSI or so that is produced on each firing. As the bolt moves rearward, headspace is lost. Often/mostly/always massive headspace loss occurs. I have seen Chinese bolts that close & move back & forth with a field gauge. I have witnessed headspace readings estimated (no gauge long enough to be certain) at greater than 20 thous. beyond Go. G.I. bolt's will also "collapse" when receiver locking lugs are not correct (commercial receivers sometimes have poor locking lug surfaces which is why we at Fulton Armory always hand lap every bolt to every commercial receiver to ensure excellent engagement before we install/set headspace), though they move rearward more slowly due to better heat treat & steel. The fact that the Chinese bolts are very soft, amplifies the problem. BTW, the locking lug helix of the Chinese receiver does agree/match the helix of the G.I. M14 bolts quite nicely. I have never had to hand lap a G.I. bolt for more than say, 15-20 minutes to get a beautiful engagement. It's quite odd. It's as though someone ground on the Chinese bolt lugs with a handtool.
2. The Chinese bolt is "too long" as it relates to the firing pin bridge of the receiver, which retracts the firing pin on loading. As the Chinese bolt moves reward, the firing pin tail also moves reward. So much so that the firing pin bridge does not effectively/at all retract the firing pin! I have seen Chinese rifles where the firing pin did not retract at all. This is quite dangerous. Add to this bolt "geometry" problem the fact that the trigger & sears, & hammers are also way too soft (hammer fall will occur) one can see the train wreck ahead.
Click HERE for more on the Chinese bolt.
Final comments:
A. One thousand rounds through an M14 is nothing. I have customers who do this in a month. The whole point of possessing fine military rifles is that their design, properly executed, provides for a durability & reliability virtually unknown in commercial products.
B. That a rifle has not failed catastrophically, nor a wing fallen off, is hardly a measure of acceptability, safety or serviceability.
C. The vast majority of Chinese M14's that come into our shop have excessive headspace, among other maladies. A very few have had too tight a headspace, which is quite odd.
Fulton Armory builds Service and Competition Grade rifles on Polytech and Norinco receivers from customer-supplied rifles. The result is a superlative M14-type rifle with a forged receiver, as close to GI as you can get.
Note to Walt: The barrel must be replaced to allow for a G.I. bolt to fit, and even then, the receiver needs relieving to safely accept the bolt! THIS IS A VERY IMPORTANT POINT! Also, the Hammer, Trigger & Sear need to be replaced.
Our package should be done all at once, or not at all. You would not believe the horrendous examples that come into the shop that were "worked on" by the local "Gunsmith," trying to fit the G.I. bolt. One needs to know what to grind, and even more importantly, what not to grind. You really would not believe it. You're too trusting to believe what I've seen, Walt
--Clint McKee
A postscript from Kirk Hays:
Having owned several of the Chinese M14S rifles, and having a set of M14 receiver gauges available to me, I have independently confirmed what Clint says about the receiver geometries. The Chinese receivers are dimensionally as good as TRW rifles in the collection of a friend. Period.
The finish on the Norinco receivers is rough on non-functional surfaces - they are ugly, and Polytech receivers are only slightly better.
John Kepler has inside information that the DCM was actually looking at using Chinese receivers for providing M14 rifles to Service Rifle competitors, and access to a steel analysis done on the recievers, showing it to be 5100 steel, which is a very good alloy for receivers, but a bit difficult to work.
--Kirk Hays
More on the Chinese bolts from Clint:
The Chinese bolts have a great deal more problems than just the heat treating. Incidentally, whether a part is cast or forged has nothing to do with whether they need to be heat treated. These bolts could be transmutated into Kryptonite, but they will still be dangerously substandard.
The problems include:
The bolt's locking lugs are cut wrong !The helixial angles are dead wrong, and thusly, they do NOT properly contact the opposing receiver's locking lugs. A very bad condition, as headspace will be lost over time. Sometimes, in only a few hundred rounds! The bolt sits very far back and away from the barrel mouth, and thus, provides very poor support to the cartridge case at its base. Bear in mind, this has nothing to do with headspace (this condition can exist even with proper headspace). The "closer" a bolt fits to the barrel mouth, the better the support of the case. Over the years, improperly manufactured barrels have shown us what can happen, even with proper headspace, when the cartridge's base is not properly supported: total case failure with catastrophic results. In the Chinese rifle example, it's the bolt sitting too far back on a proper barrel!
Next, because the bolt sits so far back in the receiver, the firing pin tail (which exits at the rear of the bolt body) is also too far rearward and thusly, the firing pin is not properly retracted by the receiver's firing pin bridge.
If you ever have an opportunity to examine a Chinese rifle, remove the op rod, and take notice of how far the bolt can move back & fro, while in battery. In many of these rifles, it's scary. Naturally, how far it will move will depend on how many rounds have been fired and just how bad the bolt was originally.
So, IMHO, forget spending a bunch, or a little, money on "heat treating" the Chinese bolts.
--Clint McKee
As to the rest, Aquaman, I was very big into M14's in the 1990's, and my very first one was a Norinco with the bobbed nose (no muzzle device).
Mine, newly imported, had bad headspace. The locking lugs on the bolt showed they were not making solid contact with the receiver as well. The detents on the rear sight wings were too shallow and would not hold the rear sight adjustment consistently. The barrel was decent and I had no complaints about the oprod. The stock was little better than a 2x4 and the trigger group had way too much slop. The hammer would not even strike the rear of the bolt solidly.
That rifle set me back $400 at the time. It was not worth it.
And that, my friend, backs up Clint's experiences. Personal experience, there, personal. It was better than a Federal Ordnance M14, but marginally. Considering the prices that Chicoms and even FedOrds go for these days, there is NO WAY they can compete, dollar for dollar, with an FAL. I can get a better FAL for less than a stock Chicom.
In other words, in response to the OP's question, there is no good cheap alternative in the M14 world when compared with the CETME derivatives or the FAL's.
Ash
