On the plastic butts, the butt plate is retained using a screw in the drain hole of the return spring tube nut. Once water gets in there and corrodes the nut to the tube, unscrewing the nut unscrews the tube too. So the butt and tube are toast! LOTS of graphite or coppa-slip chaps!
I had some functioning issues with American "reconstituted" L1A1 years ago. Had a knowledgeable person instruct me to check the gas tube that the piston rides in. I was surprised to hear that one! Figured it didn't have much to do with gas operation, just kept the piston covered. It would appear that the L1A1 gas system needs to be pretty fresh and tight to give good performance, and with the collection of well used parts that American "recons" use, that seems to be an area that can easily lead to malfunctions. These rifles are what, 50 years old now, with lots of use!? Just because they screw all that to a new receiver, does not a new rifle make. Many of these rebuilds require the gas regulator to be nearly closed to gas enough for reliable function.
I did replace the gas tube and it did seem to give me that little extra "umf" that the system needed. I had not known that the gas blocks were known for cracking!? I will now be checking that area on what rifles I come across. The good thing is we do have new pistons manufactured here. Possibly even New Surplus available from time to time. Heck, we even get "in the white" Australian gas blocks (or did a few years back), but I understand the process of setting them up, with an existing gas port in the barrel is not so easy. All things considered, guess the ports were drilled AFTER the blocks were in place? I did see some new old stock GAS TUBES on Gun Broker just last week, but think they were Metric. Do L1A1 tubes have the same thread and dimensional specs as metric? These were chrome lined, and I did not think the L1A1 had chromed tubes?
Gas plugs? Maybe new ones from DS Arms? But most of their stuff is for Metrics. Nobody in the US builds a brand new L1A1 with all corresponding bits. New Old Stock UK plugs? Not sure I have seen that in the US?
Plus, remember, a good cleaning is in order, as carbon is friction and friction kills speed and velocity. If parts are not allowed to reciprocate at intended speeds, misfeeds happen.
Newcastle,
Have I missed something on the threads?? Did you sort it out and establish the problem? or have I had a negligent discharge!!?
'Tonight my men and I have been through hell and back again, but the look on your faces when we let you out of the hall - we'd do it all again tomorrow.' Major Chris Keeble's words to Goose Green villagers on 29th May 1982 - 2 PARA
Didnt have time to get to it because of work. Bought a few snap caps in the appropriate caliber so i wasn't mucking around with live rounds. I have cycled these in my L42, DCRA and then hand cycled in my DSA FAL and they work and feed and eject fine. In the L1A1 not so much!!!!! Attachment 75479
trying to post a video of the cycling of the action. I filmed in slo-mo. Released the hold back and then it goes to slo-motion. Ejects fine but as you can see the bolt either fails to strip the next round correctly and load it OR the round gets jammed and sticks, getting jammed against the feed lips??
Here is a view of the 'loaded' magazine. As i stated these dummy rounds cycled perfectly by hand in my FAL. Attachment 75480
The "red-anodised" commercial dummies may also result in odd readings.
They appear to have a projectile profile somewhat different from service ball ammo. They are also quite soft under the anodized skin; (aluminium is like that).
I make my own dummies using "abandoned" STEEL cases available by the bucketful at many ranges. Any with signs of rust are discarded. The survivors get deprimed, washed in boiling water, dried in sunlight or in a LOW oven, then sloshed around in two-stroke fuel mix and air-dried.
THEN they are generously lubed and run through a small-based die. If you are using Berdan-primed cases, back off or remove the de-priming pin to avoid expensive crunching noises.
Seat any .30 cal surplus bullet to notional "Mil-Spec" OVERALL length and clamp in pace with a Lee Factory-Crimp die.
Holes may be drilled in the sides of the case / primer pockets bored out as desired to make them a bit more obvious.
A piece of wooden dowel closely fitted between the tail of the bullet and the web at the rear of the case is a neat bit of reinforcement. Alternately, a red-dyed polyester (fibreglass) resin can be poured into the (already bulleted) cases through the opened-up primer pocket; messy but thorough!
These steel-cased dummies last a bit longer than dummies made on brass cases.
You can do something similar for ANY ammo for which you can find steel cases: 5.56 x 45, 7.62 x 39 and 54R, etc.
A couple of dozen in each calibre will last a LONG time.
Last edited by Bruce_in_Oz; 08-21-2016 at 02:13 AM.