Just out of curiosity... why 'not' heat treat?
I'm actually kind of surprised your rifle is holding head space with no heat treat on it. (..is it maintaining head space? are you checking to see if it's growing with a complete set of gauges?) I've fired less than a mag on a raw receiver and had the head space grow considerably (not something I would recommend) You don't have to heat treat the entire receiver like DSA... I think the Austrians just spot treated their receivers. The area that takes the beating is around the locking shoulder. The shoulder itself won't deform (because it's heat treated) but the receiver in that area won't hold up.
I'm not here to preach or anything, either way it's nothing to me personally... just throwing out some info I've gained. Also, I've had an FAL fly apart on me due to bad ammo... and I can say definitively that it's not a recommended experience.
Someone said something about a receiver stub... I have some pics if that helps.
The original Aussie receivers have some issues with stretching after many rounds. This is because the receivers are only hardened in certain spots for wear but left soft for most of the receiver body to prevent cracks. The Aussie and Canadian receivers are "flame cut" instead of forged. I think this method is similar to machined billet. I'm not sure how the British receivers are formed. The Belgian receivers were originally forged from a steel similar to 1060 steel. The last Belgian receivers were cast from a steel similar to 4140 steel. The original design wouldn't allow full hardening without being prone to cracks. The newer cast receivers are made of a steel that is less prone to cracking. FN said they were able to afford upgrading the steel for the cast steel receivers because they could recycle the bad ones on site and just cast the steel again. FN was trying to compete with the stamped and welded H&K rifles in price. Early in the FAL development they made a lot of upgrades but near the end of production they cut costs of a lot of things. FN even contracted Argentina to make rifles and parts but marked FN for Belgian sales. Brazil decided to go a different route and develop their own cost cutting and compete with FN and Argentina for sales.
More Artists. Very nice work.
I will enjoy continuing to monitor this thread.
I & several friends are building Chilean kits on the last of the ORF receivers to be sold, but they are 100% FFL items & not a finish it your self deal. A person who can finish a 70% receiver that is not heatreated, to completion, with no machine tools is a dedicated person IMHO!
There are still castings for sale on Gunbroker. I hope this works out for you.
thanks for the compliments. I did cause no one had done it before with hand tools others had done it with milling machines or welding part together. I don't own a bridgeport so i did it the old fashion way
like my ar-15 0% dsa reciever I did it with a drill press and sears hand drill
re-reding this post i noted one post by C J
I posted this build on FN FAL files some clown named radio shot me down and berated me so I said F*ck him and posted on WG and here and roderus
in addition C J had said so falsehoods about me and my skills ( J/O) check CJ 's post he is not a builder or major contributor but a jealous member I can out build him and 90% for the members here and on weaponsguild
i will also note several folks built up functioning rifles with these on CNC and one guy welded the front stub to the cast before i did my hand build
sorry for the poor quality pic's they are all i have left
also i only used military full load ammo once with this build i always used 32 acp caliber adapter and weak 308 reloads
I never heat treated the build, I was approched for the build materials and kit I only retain the receiver, great paper weight
more pic's and receiver blueprint