This might be a little out of date but:
Here are a few links for BM59 information:
Copy and paste this address:
It will take a while to download, but it is the Beretta factory 4-language brochure for the BM59 that Reese used to sell for $15.
I'd save a copy of each of these, especially the last one - if you can get it to download, it oftentimes takes a while or fails.
The 4 main variants of The BM59 series are the BM59, BM59E/BM59SL, BM62, and BM69. There are sub-models of each, but here are the main distinguishing characteristics.
Only made in select-fire except for a very few early export samples and US-made SAI models.
Gas cylinder is bipod cut and has provision for gas cut-off to launch rifle grenades on almost all models (except "Mark I").
Bipod cut gas cylinder and stock.
Rubber butt pad with hatch for cleaning kit ALWAYS.
Provision for select fire, even on most semi-automatics.
Beretta "Tri-Compensator" muzzle device, either 5" or 7" long.
Most Italian military rifles were remanufactured Garands, there are a few "holy grail" rifles that are factory Beretta semi-auto remanufactured Springfield rifles. These bring over $3,000 when encountered, and I think there are only 6 known imported.
There were several military variations of this model, it was offered worldwide as both new and remanufactured with a variety of options.
These are M1 Garands modified by shortening the barrels, op rods, rear handguard, butt stock, etc., about 1/2" to convert from .30-06 (7.62X63) to 7.62 NATO (7.62X51, 1/2" = 12.7 MM). Additionally, the trigger group and receiver were heavily modified for detachable magazines and a different spring guide was installed.
The original BM59SL was semi-automatic only and nearly identical in appearance to the Garand, the BM59E adds a rubber butt pad, muzzle brake, and select-fire capability.
Many "BM59SL" models appear to be fitted with brakes and butt pads, and not all "BM59E" models are select fire.
In other words, a "BM59E" and "BM59SL" could be identical.
The Sarco kits are believed to have originated in Argentina and seem to be a combination of BM59SL and BM59E, all appear to come with brakes and butt pads but not all were select fire - the stock cuts are a tip-off even if the parts aren't included, and a pin is different (solid on the semi and hollow on the select-fire).
Rubber butt pad should have a hatch for the cleaning kit, the same as the standard BM59.
No provision for bipod due to retention of the standard Garand gas system.
As far as I know, all BM59E and BM59SL models are re-manufactured Garands except for some new ones assembled by SAI.
These models is the kissing cousin of the "Tipo II" 7.62 Garand conversions done in Italy. In fact, the op rods, barrels, and rear handguards are interchangeable between the 3 models.
Finger groove fancy stock, with no provision for cleaning kit (solid stock).
No provision for bipod on gas cylinder or stock.
Non-compensating muzzle device, although and standard BM59 device may be fitted (drop-in).
At least 2 different types of rubber butt pads, without cleaning kit hatch.
Manufactured by Beretta specifically for export, all US examples were imported by Berben.
The only factory variations are in the butt pads.
Marked ".308W" for caliber.
Based on the BM59 "Mark I" these were made for civilians and imported in 1969.
Unique gas cylinder that is bipod cut but does not have provision for gas cut-off.
May be fitted with a bipod.
May be fitted with either a 5" Tri-Compensator or 'BM62' muzzle device.
Varying rubber butt pads, sometimes a "Shotgun" type sometimes BM59 military type.
All US examples were imported Benet Arms.
Any FACTORY semi-automatic BM59 type rifle should have a serial number
below 4,000, whether it is a Beretta or SA, Inc.
All of the Beretta "semi-auto" receivers were numbered this low, perhaps below 3,000. This
includes all SAI BM59 variations, Beretta BM62s, and Beretta BM69s.
"Fake" BM59s almost always have Garand gas cylinders, no muzzle device or a rudimentary flash hider, standard Garand steel butt plates, and 'high' serial numbers.
With SAI/Reese selling parts for many years, it is common to see BM62 and BM69 rifles "militarized" with Tri-Compensators, bipods, cut-off gas cylinders, etc.
This is generally seen as detracting from the collector value of the gun but shouldn't detract from shootability aside from the added weight of accessories.
The wooden folding stocks marketed for the M14 by SAI and Reese Surplus originated on the BM59.
Most parts interchange across the board for the entire BM series.
A BM59 Tri-Compensator drops onto a BM62, stocks mostly interchange, most mechanical parts are the same.
Most parts are marked "P B BM59" even if fitted to other BM series rifles.
All factory BM series receivers - Beretta or SAI - are forged by Beretta in Italy.
SAI finished some raw and/or semi-finished receivers in Illinois.
Firing pins are standard Garand, extractors are unique for magazine clearance.
Recoil springs are available from Wolff Springs ( http://www.gunsprings.com/ ).
All trigger group parts (hammer, trigger, sear, safety, trigger guard, etc.) are standard Garand, except the obvious magazine catch parts.
As far as I know, all factory BM series rifles have stripper clip guides and accept standard NATO 7.62 stripper clips. In fact, this is how the Italians loaded them, the rifles were only issued with 1 magazine!
Because of this, magazines are a bit rare and pricey - starting at around $75 and working their way to over $100 each. With that said, Sarco sells used ones for substantially less, but they might not be
All factory magazines have chrome followers as far as I know. Some may be encountered with plastic followers, these are 'aftermarket' but I think used some factory parts.
It is possible to modify a BM series rifle to use standard M14 magazines, but it requires fabrication of a front magazine catch and modification of the rear magazine catch.
BM59 magazines are larger than any other 7.62 NATO rifle's magazines and don't fit into most magazine pouches.
The "Israeli FAL magazine pouch" available from http://gunthings.com/ for $6 are said to work well with BM59 magazines.
As far as parts suppliers, Reese Surplus and Andy in Italy are no longer in business. Gun Broker is going to be your main supply.
If you need receivers, assembly, parts fabrication, or customization, I'd suggest Tim at Shuff's Parkerizing ( http://www.shuffsparkerizing.com/ )
I'd suggest a 5-inch "BM69" Tri-Comp (bayonet lug under the screw) for a BM62 if you can find one, its a drop-in and fantastic compensator and flash hider.
Standard Parts ( https://www.standardpartsllc.com/productcart/pc/viewcategories.asp?idCategory=26 ) seems to have Beretta parts. Inventory seems to vary depending on what they can get.
From my understanding, the main parts that break are the same as on Garands - firing pins and extractors.
http://www.machinegunboards.com/forums/index.php?showforum=7 is a dedicated BM59 message board, although it is slow the guys there can help with a lot of parts, information, and advice.
http://forum.shuffsparkerizing.com/forumdisplay.php?22-BM59-Forum is the new Shuff's Parkerizing BM59 forum that I'm a moderator on.
Enjoy your rifle!
Formerly "Eli" - vBulletin won't allow 3-character user names!
I buy "Tipo II" and BM59 parts