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1911Ron
December 02, 2017, 20:06
Curiosity has me wondering about the effective the sand cuts were? I know about the theory and all but was it really effective and where did the sand go? Into the HTS area?

NHBandit
December 03, 2017, 08:28
FN must have decided they worked because at one point several years ago I bought a bunch of "inch pattern" sand cut carriers from one of the Tapco getting out of FALs blowout sales and one of them had Belgian proofs on it. Was told by the experts here it was very late FN production. Sold it here in the marketplace for pretty good bucks.

J. Armstrong
December 03, 2017, 08:34
When used as originally intended, i.e. in conjunction with a lot of grease. the inch sandcuts were quite effective if we are to believe the military board reports as related in Stevens.
OTOH, while FN did indeed offer sandcuts, most particularly the simplified cuts later used by Israel, it is interesting to note that apparently no country ever adopted them . Israel only used them as part of their forward assist charging handles.

bigstick61
December 03, 2017, 18:06
Some of the FALs from the earlier (and distinctive) Libyan contract have sand-cuts of the zig-zag style based on photographs. I've seen a commercial 50.00 with them as well. One thing I've wondered about the Belgian parts is whether or not the bolts are also sand-cut, or just the carriers, and what the sand cuts look like on the underside of the bolt carriers compared to inch and Israeli ones.

Regarding grease, I've read British publications that call for stripping all grease and oil from all parts in anticipation of sandy conditions (and discuss using the heat from the sun to help with removal). Were the sand cuts meant to function with grease, or were they meant to function dry like the British manuals seem to indicate?

bigstick61
December 03, 2017, 18:10
When used as originally intended, i.e. in conjunction with a lot of grease. the inch sandcuts were quite effective if we are to believe the military board reports as related in Stevens.
OTOH, while FN did indeed offer sandcuts, most particularly the simplified cuts later used by Israel, it is interesting to note that apparently no country ever adopted them . Israel only used them as part of their forward assist charging handles.

The sand cuts were not needed for that purpose, so it would seem that they adopted them in addition to adopting the FA charging handle. Aside from the rectangular cuts on the sides, there are also cuts on the underside of the bolt carrier, different from the inch cuts. I don't think that the bolts had sand cuts, but the bolt carrier had a cut on the underside corresponding with the location of the top forward cut on the inch bolt (which might have served the same function as the bolt sand cut), which is absent on the inch carrier.

I wonder what difference, if any, there is in effectiveness of the two styles.

plinker
December 03, 2017, 19:08
Saw this in another thread, not sure that dirt qualifies as sand though. Interesting either way.

While the AK47 is easily capable of firing when in a filthy condition, an FN with dirt in the breech area is guaranteed to suffer from stoppages

http://www.falfiles.com/forums/showthread.php?t=407710&highlight=rhodie+manual

J. Armstrong
December 03, 2017, 19:50
The sand cuts were not needed for that purpose, so it would seem that they adopted them in addition to adopting the FA charging handle.


The simplified sand cuts are nothing more than the "interrupted" side rails on the carrier. That is exactly what the FA handle acts on. I have always assumed ( Yeah, I know ......:) ) that the Israelis simply designed the FA handle to correspond with those cuts, as I believe the cuts were developed by FN before the Israelis FA handle

J. Armstrong
December 03, 2017, 20:06
Regarding grease, I've read British publications that call for stripping all grease and oil from all parts in anticipation of sandy conditions (and discuss using the heat from the sun to help with removal). Were the sand cuts meant to function with grease, or were they meant to function dry like the British manuals seem to indicate?

Branch Memorandum, No ARDE (P.3) 3/55 is covered in Stevens "UK & Commonwealth FALs starting on pg 97.

If I am reading their conclusions correctly, as of that date, the bolt cuts alone caused a significant increase in reliability; however, due to noted deficiencies in the test protocol, the board felt that the results were inconclusive and further tests in Libya confirmed that best results were achieved when a the all the sand cuts were present in conjunction with "liberal" application of graphite grease. That being said, we all know what a bad idea graphite grease can be if it migrates into the rifles chamber, and as I can't find mention of the grease in later tests, I assume ( again :rolleyes: ) that the ARDE/British Army did not in fact recommend or use grease subsequent to 1955 in actual service use.

embatp
December 03, 2017, 20:57
During the X8 trials both forward assist and sand cuts were tried.... I believe the Fal book states that having both offered no more reliability than having just one or the other....so the brits went with the cut carrier and the Izzys with the forward assist....

the gman
December 04, 2017, 04:34
I can tell you from personal experience with the L1A1 in the deserts of Saudi, Kuwait and Iraq during Desert Shield/Storm/Saber, that they don't run worth a shit if they are dry. We were all told that it was vital to not lube the rifle as the lube would pick up sand and dirt leading to stoppages. Well, we followed the manual to the letter and on our first range day, not ONE L1A1 ran thru a mag without stoppages left and right.

Threw some lube in there and started running like champs; so much for the collective wisdom of the military... :uhoh: Almost ashamed to admit it but after a few more range days when it became clear the dear old L1A1 was a bit temperamental in regards to functioning in the desert, I snagged the first AK I could find and carried that until the official end of hostilities. :(

bigstick61
December 04, 2017, 04:34
The simplified sand cuts are nothing more than the "interrupted" side rails on the carrier. That is exactly what the FA handle acts on. I have always assumed ( Yeah, I know ......:) ) that the Israelis simply designed the FA handle to correspond with those cuts, as I believe the cuts were developed by FN before the Israelis FA handle

Looking at pictures, I've found some that show a shallow rectangular cut on the bolt carrier side between (and obviously above) the rail cuts (the rail cuts themselves are symmetrical; if the sole purpose was for FA use, only the left cut would be needed). The ARS Israeli parts page has a picture of one like that as seen below, but in looking up pictures right now some stated as being Israeli bolt carriers don't have that, only the rail cuts.

https://www.arizonaresponsesystems.com/store/store-fal-izzy/store-fal-izzy-boltcarrier-ars.jpg


Whatever the case, they without a doubt have sand cuts along the underside of the carrier as shown below (Mark highlighted the cut areas in green):

http://www.arizonaresponsesystems.com/wp/fal/fal-izzy-boltcarrier-01.jpg

One thing I don't know is whether or not the Israeli receivers were sand cut as well, same with FN receivers used with the zig-zag style sand cut bolt carriers.

bigstick61
December 04, 2017, 04:44
I can tell you from personal experience with the L1A1 in the deserts of Saudi, Kuwait and Iraq during Desert Shield/Storm/Saber, that they don't run worth a shit if they are dry. We were all told that it was vital to not lube the rifle as the lube would pick up sand and dirt leading to stoppages. Well, we followed the manual to the letter and on our first range day, not ONE L1A1 ran thru a mag without stoppages left and right.

Threw some lube in there and started running like champs; so much for the collective wisdom of the military... :uhoh: Almost ashamed to admit it but after a few more range days when it became clear the dear old L1A1 was a bit temperamental in regards to functioning in the desert, I snagged the first AK I could find and carried that until the official end of hostilities. :(

My one experience with a FAL without sand cuts after getting hit by a windstorm (not quite a sandstorm, but enough to get sand, including gritty and also the fine, powdery stuff into every crevice and all over everything) was that it would not go through more than a couple of rounds without a stoppage. The bolt carrier would drag enough that it did not have the energy left to fully strip the next round from the magazine. It had to be pulled back and released once or twice and then it would chamber the round. Rarely could I get off two rounds without a stoppage. It usually happened after each shot. When we got back the rifle was a huge PITA to clean. I'm not sure what sort of lubrication it had, as the owner did not know much about FAL maintenance at the time, but it was either dry or had a little bit of Rem oil. The sand that day was so bad that it even caused my Mosin-Nagant's bolt to seize. I had to clean that rifle three times to get all of the sand out once I finally managed to remove the bolt (I forget how I did it; not even whacking it with a mallet helped initially). Rifle was a FN 50.63, one of the Howco/Gun South imports.

Another issue I've seen is that if enough sand gets in the BHO, lubed or not, it doesn't always travel upwards fast enough to catch the bolt after firing the last round, although this of course would not be an issue on a SLR since it lacks the last-round BHO feature.

J. Armstrong
December 04, 2017, 08:18
[QUOTE=bigstick61;4509203]Looking at pictures, I've found some that show a shallow rectangular cut on the bolt carrier side between (and obviously above) the rail cuts (the rail cuts themselves are symmetrical; if the sole purpose was for FA use, only the left cut would be needed).

Exactly so.

1911Ron
December 04, 2017, 19:18
The FA on the Izzy was a separate cut from the sand cuts, plus the charging handle pin was longer (duh) to reach the BC.

J. Armstrong
December 04, 2017, 19:42
The FA on the Izzy was a separate cut from the sand cuts, plus the charging handle pin was longer (duh) to reach the BC.

You have to be careful when you refer to carrier sand cuts. When discussing the FA handle, we are NOT talking about the common, L1A1 style cuts, we are talking about the "simplified" carrier cuts such as shown in bigsticks pix. IN this case, the sand cuts and FA cuts ( only one cut would be needed for te FA, of course ) are one and the same.

1911Ron
December 05, 2017, 08:37
You have to be careful when you refer to carrier sand cuts. When discussing the FA handle, we are NOT talking about the common, L1A1 style cuts, we are talking about the "simplified" carrier cuts such as shown in bigsticks pix. IN this case, the sand cuts and FA cuts ( only one cut would be needed for te FA, of course ) are one and the same.

I stand corrected, I was unaware and "assumed":facepalm: they were separate. Thank you for the correction:)

gunplumber
December 05, 2017, 08:47
I can tell you from personal experience with the L1A1 in the deserts of Saudi, Kuwait and Iraq during Desert Shield/Storm/Saber, that they don't run worth a shit if they are dry. We were all told that it was vital to not lube the rifle as the lube would pick up sand and dirt leading to stoppages. Well, we followed the manual to the letter and on our first range day, not ONE L1A1 ran thru a mag without stoppages left and right.

Threw some lube in there and started running like champs; so much for the collective wisdom of the military... :uhoh: Almost ashamed to admit it but after a few more range days when it became clear the dear old L1A1 was a bit temperamental in regards to functioning in the desert, I snagged the first AK I could find and carried that until the official end of hostilities. :(

My experience as well, running FALs in the AZ desert. Run them wet. Wear glasses.

J. Armstrong
December 05, 2017, 22:17
Looking at pictures, I've found some that show a shallow rectangular cut on the bolt carrier side between (and obviously above) the rail cuts (the rail cuts themselves are symmetrical; if the sole purpose was for FA use, only the left cut would be needed). The ARS Israeli parts page has a picture of one like that as seen below, but in looking up pictures right now some stated as being Israeli bolt carriers don't have that, only the rail cuts.

https://www.arizonaresponsesystems.com/store/store-fal-izzy/store-fal-izzy-boltcarrier-ars.jpg


Those rectangular side cuts are interesting - I don't recall ever noticing them on any of the sand cut carriers I had. Looks almost like they wanted more clearance between the carrier rails and receiver rails, which would make sense.

gunplumber
December 08, 2017, 08:07
FWIW, I just did another run of Izzy FA carriers with the sand cuts and the FA cuts. Converted IMBELs.

http://www.arizonaresponsesystems.com/wp/fal/fal-izzy-boltcarrier-machine-01.jpg

http://www.arizonaresponsesystems.com/wp/fal/fal-izzy-boltcarrier-machine-02.jpg

http://www.arizonaresponsesystems.com/wp/fal/fal-izzy-boltcarrier-machine-03.jpg

http://www.arizonaresponsesystems.com/wp/fal/fal-izzy-boltcarrier-machine-04.jpg

pl521
December 08, 2017, 08:18
Dang GP, you're putting that Kurt vise to good use! Nice.

kotengu
December 08, 2017, 08:57
Dang GP, you're putting that Kurt vise to good use! Nice.

Yep - forget the cuts. Beautiful vise!!!

gunplumber
December 08, 2017, 09:25
The forward 70 degree triangle cuts are an example of why I wanted the swivel base too. I have need for repeat angle cuts with some frequency.

There is a little play from the t slot bolts to the base, so I zeroed the vise to the swivel base, locked it down, and turned the whole base to get it parallel. So now I really can use the degree marks to return to 0 - at least within .003" over 4'. Better than that and I need to get out the alignment bar and edge finder.

The Kurt work stops made set up sooooo easy. Calculate the offset for cutter diameter, zero the DRO, and then one after the other. The slowest part was watching the feed and squirting the cutter if it started to smoke.

When I inquired on this vise - "is really good enough to justify the high price?", the unanimous answer was "yes, yes it is!"

Had I known how much easier it would be than what I thought was decent Taiwanese, I'd have bought it years ago. But then I'd have a D80 and not the new DX6 . . . This thing rocks. I haven't had any problem with work piece wanting to rise out of the jaws.

So side question - Bottom cuts were no problem - I used a 1/2" carbide and they went quick.

FA cuts I used a 3/16 carbide and it went pretty well, but there was a noticeable change in hardness on the front ends of the cut.

The groove on the outside, right above the rail - I did the first 2 carriers with a Keo Kobalt keyseat cutter, that I use for lightening cuts on L1A1s. It was not happy. Rough(ish) finish and heated up fast. It was a used cutter but looked ok. Tried my spare, same thing. I was running 400 rpms and slowest feed.

On a whim I tried a HSS cutter - it cut much cleaner with less heat. I use a spray bottle and the moment I see a wisp of smoke from the cutting oil, I sprayed it again. I kept increasing the feed and it didn't seem to care. I mean, it was still slow, but 3 times faster than the carbide with less heat. The DRO just says feed= .5, 1, 1.5, etc, so I don't know what it was in ft/min. But about 2 minutes to traverse the side of the carrier.

Is there a reason on such hard metal that a HSS cutter would do so much better than a HSCo?