CliSwe, I think you’re putting the cart before the horse: the high ROF was part of the pre-war spec for the 8-gun fighters, based on calculations of anticipated engagement times at 300mph. Lighter weight is simply the necessary result of the higher ROF, not the other way around,
Hi Guy’s
Canada took all thier M1919A4 Browning Guns and changed them up to 7.62mmX51 NATO as C1 and C5 in the late 1960 till early 2000 The Brownig was replaced By the C6 (FN Mag 58)
Cheers Gerry
So were a lot of ground M1919’s in the US services.
Jenkin wanted to know about the .303 RAF version, which was most unsuitable for such a conversion.
To summarise all the points made by other posters, and some other features added by the RAF.
Most of the gun would have had to be replaced.
And, there was no need for a belt-fed air cooled LMG in the cut-back British services.
Another way of thinking about the OP (Jenkin) question of why not?’ is this.
Until about end 1943 in the Pacific, and end 1942 in Europe/Nth Africa adaptation of of free-mounting 0.5" ANM2’s and their ammunition, from downed US-made aircraft was very common - but for LAA purposes.
This pretty much ceased once Allied air supremacy became a common feature in all theatres. At the same time Quad mounts on half tracks and trailers - using standard M2HB’s became very common. Add in the advent of plenty of 20mm Oerlikons and Polstens as well.
So, local adaptation of ‘found’ 0.30" aircraft Brownings for ground use as LAA weapons, just never took off. Not effective enough.
The reality for the .50 Browning M2 is that it was acceptable as a fixed air-to-air gun in WWII, when 6 or 8 were carried. It was not even the most effective 12.7mm aircraft gun of WWII. Russia’s were lighter, just as reliable, fired faster, and hit just as hard.
Just for completeness the RAF’s adaptation to .303 ammunition, of the fixed-mount M1919 .30 gun involved an almost complete redevelopment of the gun. All the in-service 0.303 guns were entirely made in Britain.
the timings and delays of the firing mechanism*
primary extraction for the rimmed round*
A new muzzle attachment, to help increase RoF, and then modified because of increased fouling from ‘cordite’ propellant.
Even lighter moving parts* than the USAAF version > RoF.
the same gun was used in all the turretted installations in RAAF bombers. Single free guns were mostly the VGO.
This latter being the only RAF aircraft gun adapted for ground use in nay numbers, to be mounted on pintles for use against aircraft by the SAS, and using the RAF’s own TI and API rounds, and where it’s high RoF matched the role of course.
During WWII I nursed 4 Browning 303’s in the back of a Wimpy (wellington) then Lancaster (Lank) (Tail end Charlie) . I found them very reliable in operation (though a little bit noisy.) Cooling was not a problem as at 29,000 feet the outside (and inside) temperature was -40.
We had them mounted in the Frazer-Nash or Bolton-Paul turrets (one hydraulically driven the other electric). Not much difference between them, as long as they worked.
I was able to strip down a 303 and assemble it - Blindfold - in less than one minute - at 85 yoa now it would probably take me a week.
Towards the end of the war the 303 was swapped over to the .5 but I think I preferred the .303.
Don’t like guns now, or wars - Nasty things.
Stonkey.
Thank you for this info Stonkey.
What was the effective range of the 303? I would guess you would be wasting ammo over 200yds?
And did you ever hit or shoot down a German plane with the thing?
cheers,
Saxon
From my grandads notes (Air Gunner on Blenhims then rear gunner on Wimpys and later Lancs served 1938-1960) he rarely fired all four brownings at once as the barrels drooped so he fired in pairs.
He does not say whether he actually shot one down as most raids were night time and you had limited vision of an incoming aircraft (although he does comment that he thought the flak was pretty coloured along with the tracer), more that you tried to keep them away from you ‘make you look dangerous so they go for an easier target’
Hi Timbo,
This is a bit off-topic, but the OP was 3 years ago 
It sounds like you have info on the deployment of 20mm Oerlikons and Polstens!
I had researched British Army use of 20mm AA guns, and found them difficult to nail down.
Best I can tell, the Oerlikon was available in England from 1940 but perhaps only for RN use? It seems certain it was used by the British Army, but I can’t find it listed in any OOB or solid reference.
I have a couple of vague references (and a photo or two) to the Oerlikon being used in Italy.
I also have a reference to Support Battalions being equipped with 16 LAA 20mm, in mid 1943.
I know the British Army (LAA and SAS) used plenty of captured Italian Breda 20mm from 1941.
The first reference to the 20mm Hispano is Airborne troops training with it in May 1943.
Airborne switched to the 20mm Polsten which seems to arrive in large numbers and in many different types of mountings and configurations around March 1944.
I’d be grateful for any additional information.
(Mods, if this is too ‘off-topic’ let me know and I’ll start a new thread, thanks)
Cheers,
Saxon
You’d probably get better responses in a thread with a title that reflects the weapon / use you’re interested in than in this thread.
If you’d like, post a suitable thread title and I’ll start a separate thread under that title.
Hi Saxon,
Thanks for your reply. To answer your question re the range of the Browning 303, I don’t know! as I don’t think we were ever told? We used to align our 4 rear turret guns on a target at 1500 yds by removing the breach-blocks and looking down the barrels.
I never ever saw a German kite. I was 14 in 1939 when they started the war, (not my fault!) When I joined the RAF in 1943 my training lasted over a year, I started off as a WOP/AG (Wireless Operator Air Gunner) and then a straight AG as the WOP/AG was scrapped.
On finishing training etc;was posted to Bomber Command, but I got Rubella (German Measles) and was kept in isolation for 10 days. When I emerged from hospital my crew had picked up another AG and moved on. As no one wanted a sprog AG I spent most of the rest of the war in testing kites that had been repaired after being shot up during raids over the pond. I also went on trips to scatter Windows (strips of silver paper) to fool the krouts radar. I was shot at twice, by our own Navy (shoot first - ask questions later if necessary) B*******.
Stonkey.Hi Stonkey,
It sounds like you had a pretty good war!
It’s a good job those RN lads were rubbish shots huh!
Both of my Grandfathers were part-time volunteer firemen before the war started, so they were kept in the fire brigade for the whole war. One of them in London the other in Somerset. I had at least one Great-Uncle in the BEF. He was the last one out of Dunkirk (supposedly) and I believe he survived the war.
The older I get, the more I appreciate your generation, and what you did.
Thank you for your service (Salute).
Saxon
Aw Shucks wuz nuthing really.
Keep Smiling,
Stan.
The Polsten was issued late in WWII in the European theatre, It was a lightened and simplified (number of parts down to about 40%) Oerlikon. Initially to paras and etc. Same drum and ammo.
the Allies did not need much in the way of super good very light AAA by 1943, and what they did have was fine. The 40MM bofors L60 plus the quad and twin .5"M2HB, and later the Polsten. noting that the kerriosn predictor for the bofors L60 was very good and the LAA regiments thus far outperformed any German units.
The Germans DID need superb LAA by 1942/3.