Titan ReloadingRotoMetals2MidSouth Shooters SupplyWideners
Lee Precision

Results 1 to 19 of 19

Thread: Lee Enfield #4 Two-Groove Keyholing at 25m

  1. #1
    Boolit Grand Master 303Guy's Avatar
    Join Date
    Oct 2008
    Location
    New Zealand
    Posts
    9,019

    Lee Enfield #4 Two-Groove Keyholing at 25m

    First time I've seen this but have heard about it. The guys at the range had never seen it before either.

    Keyholing and the same bullet in another two-groove.

    Note the single bullet that did spin up.

    It obviously to me that the bullets were skidding the rifling and simply not spinning up to speed. It just so happens that I know about skidding of the rifling in a two-groove, having done some tests in the past.

    So I took it home and considered relegating it to the scrap pile (or changing the barrel). But, I did some bore diameter measuring and found that the muzzle was trumpeted - which I knew about, it having had some bore rust, mostly at the muzzle end. I also found that the bore was tight in the middle area. It was also a bit rough in that area.

    I first fired an identical load and found that it skidded and went through the catch medium sideways.


    Then I lapped the bore until I could no longer feel any difference in resistance throughout the bore. I then counter-bored the muzzle up to the point that I had found the trumpeting to begin.

    Then I did some tests. Now at this point, I had been reading up and the consensus was that some 303's just don't like boat tail bullets and that they will sometimes keyhole with them. The wisdom is to use flat base bullets. I can understand the flat base bullets being more accurate than boat tails b ut keyholing? Well yes, if one sees what's actually going on in the bore. But why this two-groove and not my other one?

    Well, here's why. The guilty two-groove has a larger bore and a restriction in the middle area. This translates into rifling skid. Now, sometimes a skidded bullet will eventually spin up and exit the muzzle following the rifling. I know this because I have done tests and recovered the bullets.

    One can see by the striations that these bullets did eventually spin up.


    Apparently, what happens is that a while a boat tail might skid the rifling, a flat base has the more substantial base which will engage the rifling. Then again, a skidding bullet is still undergoing a spinning force as it progresses down the bore. In this particular rifle however, with a narrower bore which then opens up a little, only by .001", loses its grip on the bullet so it never spins up fully. Now, I can tell by the target impact that there is some spin in the bullet because they are hitting sideways and not just tumbling head over heel.

    So after lapping the bore, I fired a few bullets down the bore that I knew would skid. And as I expected, they had spun up fully and penetrated the catch medium nose first. I then used a powder that produced a lower pressure and an undersize bullet (308 in a 303) and it engaged the rifling. Next, I increased the charge to get it to skid which it did but it still spun up. I then loaded a .311 bullet and fired it and it engaged the rifling. This is with flat based bullets. I am yet to put a boat tail through it after the lapping.

    This is what a fired bullet should look like.


    This by the way, is a .308 bullet in an oversize 303 bore. The second skidded bullet above was loaded to the starting load.

    The takeaway here is that a keholing problem can be fixed by ensuring that the bore does not have a counter taper or constriction in the center area and by reducing the powder charge to the point where skidding does not occur. This applies to cast boolits. I had previously fired cast boolits in this rifle and they went through just file but with low powder charges. I would suspect that with the trumpet muzzle, accuracy would have been poor.



    Here one can clearly see full engagement of the rifling with no skid at all.
    Last edited by 303Guy; 12-04-2022 at 10:14 PM.
    Rest In Peace My Son (01/06/1986 - 14/01/2014)

    ''Assume everything that moves is a human before identifying as otherwise''

  2. #2
    Boolit Master
    Join Date
    Jul 2014
    Location
    Arizona
    Posts
    3,651
    My Mk 4 Long Branch will Keyhole with light cast Boolits if fired under 1000 FPS.
    But tight fitting Heavier Cast Boolits like 170 or heavier work better and shot around 1200 FPS or better.
    As far as jacketed Bullets.
    They all shoot great but the heavier ones shoot better.
    Again,
    You can't shoot them too slow.
    Also on the cast Boolits.
    Using linotype or harder lead works better and you can shoot them faster.

  3. #3
    Moderator


    Join Date
    Apr 2014
    Location
    Way up in the Cascades
    Posts
    6,771
    Great write-up. 303Guy. As the owner of several L.E.s I found it very interesting. I do know that 2 groove barrels can be made to work, but the first time I saw one in the rack of a Big 5 Sporting Goods store I was so taken aback seeing what I saw peering through the bore, where I expected to see 4 grooves, I said, "Uh-uh" and handed it back.

    DG

  4. #4
    Boolit Grand Master 303Guy's Avatar
    Join Date
    Oct 2008
    Location
    New Zealand
    Posts
    9,019
    Keyholing with light boolits and light loads? Interesting. I do have a problem with the large tapered throat for cast. I found a target from last year that I had forgotten about. The load was a fat 220gr two-diameter casting and 5gr of clays. This one being a five-groove.



    Thanks Der Gebirgsjager. I have had good accuracy with one of my two-grooves. You may remember me mentioning it. It's the one with a 'rust textured' bore. And it is shooting boat tails. But the boat tail is not very pronounced. I did shoot a group with 174gr FMJ boat tails and it made circle group.



    These were light loads - 28gr H4895. I assumed too slow to stabilise such a long bullet but wondered whether they would have settled down over a longer distance. That was in the rough bore. This rifle doesn't work with cast.

    You can see why


    I would like to get these to shoot 150gr bullets at higher velocity just to get a flatter trajectory. My idea is to have one load for each rifle. I counted them today and I have 13 Lee Enfields. None are in battle dress though. One for distance shooting with jacketeds, another for paper patch, another for cast for plinking and another for cast for competition and so on. Cast is basically essential for range work. Paper patch is too much work and jacketeds cost too much.

    So hard cast is the way to go for higher velocity? Something that I have found is that if the boolit are too soft, they will upset between the case mouth and the throat. That of course distorts the boolits so I would expect them to shoot poorly. I happen to have a hard alloy in my pot so I shall cast a few hard heavies and try them.

    I should mention that my eyes are changing and I thought that the peep sights would be just the ticket. The last time I looked through a peep sight I could see the front post sharply. Not any more. So I made and fitted a tube over the frond blade. Now I can aim it again. I plan to hunt with it. It has a really nice balance and I find I can hold it still on the target off the shoulder.
    Last edited by 303Guy; 11-23-2022 at 12:25 AM.
    Rest In Peace My Son (01/06/1986 - 14/01/2014)

    ''Assume everything that moves is a human before identifying as otherwise''

  5. #5
    Moderator


    W.R.Buchanan's Avatar
    Join Date
    Mar 2011
    Location
    Ojai CA
    Posts
    9,388
    I had mine bored out to .35-303. It now has 4 grooves.

    Randy
    "It's not how well you do what you know how to do,,,It's how well you do what you DON'T know how to do!"
    www.buchananprecisionmachine.com

  6. #6
    Boolit Grand Master 303Guy's Avatar
    Join Date
    Oct 2008
    Location
    New Zealand
    Posts
    9,019
    I would very much like a 35/303. I don't actually have a use for one but I believe that with the correct throating, it would make a superb cast boolit rifle. I'm sure one could get a barrel blank and do something with it. But, I've got enough Lee Enfields to play with already and I've already shown that at least two of them shoot cast quite well. Yesterday I found a fired boolit from my five-groove and it indicates a perfect bore fit with no sign of canting, which has been a problem I've encountered, even with jacketeds.

    Oh, I mentioned elsewhere a No4 being chambered in 300 Win Mag. This rifle was a 303 target rifle using a .308 target barrel, so a bit tight in the bore. And firing standard 303 target rounds. 308 barrels are more readily available than most. Just a thought. Mind you, the chamber reamer would likely have been custom ground I would emagine.
    Last edited by 303Guy; 11-23-2022 at 08:37 PM.
    Rest In Peace My Son (01/06/1986 - 14/01/2014)

    ''Assume everything that moves is a human before identifying as otherwise''

  7. #7
    Moderator


    Join Date
    Apr 2014
    Location
    Way up in the Cascades
    Posts
    6,771
    2 items: 1. Whooooie! A No.4 in .300 Win. Mag? Didn't the Brits decide that the .308 Win. Was a bit "iffy" in the No. 4, and it took a better grade of steel for the Indians to make it work? Is it yours? How many times have you shot it, and is that with factory loads or factory-level loads? Is the headspace holding up? 2. I see you're shooting lighter weight bullets. What's your experience been with heavier bullets/boolits? I've had good luck with both jacketed and cast .303s in 200, 215, and 220 gr. weights over the years, mostly (not entirely) in No. 3s.

    DG

  8. #8
    Boolit Grand Master 303Guy's Avatar
    Join Date
    Oct 2008
    Location
    New Zealand
    Posts
    9,019
    Here is the front tunnel sight I fitted.



    I can see so well through it. The blade is still there but I can't actually see it when aiming.
    Rest In Peace My Son (01/06/1986 - 14/01/2014)

    ''Assume everything that moves is a human before identifying as otherwise''

  9. #9
    Boolit Grand Master Texas by God's Avatar
    Join Date
    Mar 2016
    Location
    Texas
    Posts
    12,826
    Aren't the Ishapore .308 rifles considered a No.1 action- not a No.4? Albeit with better steel?

    Sent from my SM-A716U using Tapatalk

  10. #10
    Boolit Master
    Join Date
    Jul 2014
    Location
    Arizona
    Posts
    3,651
    A friend had a .308 Enfield No4.
    But it was a Parker Hale
    Or converted by PH

  11. #11
    Moderator


    Join Date
    Apr 2014
    Location
    Way up in the Cascades
    Posts
    6,771
    Quote Originally Posted by Texas by God View Post
    Aren't the Ishapore .308 rifles considered a No.1 action- not a No.4? Albeit with better steel?

    Sent from my SM-A716U using Tapatalk
    Yes. An ordinary No.1 is considered weaker than an ordinary No.4. There has been a lot of head scratching about why the
    Indians didn't go with the No.4. I surmise it was because their arsenal was already making the No.1 and had been for many years. Supposedly the new steel they employed was a vanadium alloy, and it's increased strength was enough to handle the .308. The British did issue No.4 .308 Win. sniper rifles, but did not have a general issue .308 No.4. I think the idea was originally for a mass conversion and re-issue of No.4s in .308, but they decided against it after some field trials. I'm hoping .303 Guy will return and bring us up to speed on the .308 No.4s, and the .300 Win. Mag. No.4.

    DG

  12. #12
    Boolit Master
    Join Date
    Nov 2017
    Location
    brisbane ,qld,australia
    Posts
    1,795
    Some # 4 rifles were commercially converted to 243 Winchester by Sako of Finland ......and there are still lots of them about ,so they didnt blow up..........There are various stories about the Indian 308 rifles,and it appears that the steel and heat treatment was no different to the 303 rilfes.........what was done was to change the proof procedure to eliminate the "one round shot with an oiled case"......and substitute two rounds with dry case.Problem solved.

  13. #13
    Moderator


    Join Date
    Apr 2014
    Location
    Way up in the Cascades
    Posts
    6,771
    Quote Originally Posted by Texas by God View Post
    Aren't the Ishapore .308 rifles considered a No.1 action- not a No.4? Albeit with better steel?

    Sent from my SM-A716U using Tapatalk
    Yes. An ordinary No.1 is considered weaker than an ordinary No.4. There has been a lot of head scratching about why the
    Indians didn't go with the No.4. I surmise it was because their arsenal was already making the No.1 and had been for many years. Supposedly the new steel they employed was a vanadium alloy, and it's increased strength was enough to handle the .308. The British did issue No.4 .308 Win. sniper rifles, but did not have a general issue .308 No.4. I think the idea was originally for a mass conversion and re-issue of No.4s in .308, but they decided against it after some field trials. I'm hoping .303 Guy will return and bring us up to speed on the .308 No.4s, and the .300 Win. Mag. No.4.

    DG

  14. #14
    Moderator


    Join Date
    Apr 2014
    Location
    Way up in the Cascades
    Posts
    6,771
    Quote Originally Posted by john.k View Post
    Some # 4 rifles were commercially converted to 243 Winchester by Sako of Finland ......and there are still lots of them about ,so they didnt blow up..........There are various stories about the Indian 308 rifles,and it appears that the steel and heat treatment was no different to the 303 rilfes.........what was done was to change the proof procedure to eliminate the "one round shot with an oiled case"......and substitute two rounds with dry case.Problem solved.
    Always glad to hear from the folks down under, John. I own more than several L.E.s of both models, and have worked on many, but would never claim to know as much about them as someone from a Country that actually used them. I can certainly see how a L.E. could be converted to .243 and function properly, especially with the new barrel that would be required. And, Sako is strictly first class, and they wouldn't turn out anything that wasn't also first class.

    The first problem I encountered in gunsmithing L.E.s was the headspace problem. Seems like any of them that are used long enough with the issue or equivalent ammo will develop excessive headspace. That was compensated for in the No.4 by the replacement bolt heads in increasingly longer lengths-- but even there eventually they have to be re-barreled when one runs out of sizes. In the older No.1 I was usually successful in correcting the headspace by trying replacement bolt bodies, but there are about a dozen other methods that have been tried, some not so successful or wise. The long safety lug in front of the bolt handle likes to batter the part of the receiver it rests against and gradually the headspace increases. Nevertheless, I love the old No.1 almost as much as our contemporary .30-40 Krag, which was also prone to much the same issue with shortening of it's one bolt lug. So, I'm just waiting for some enlightenment here, as a L.E. in .300 Win. Mag. seems a bit over the top to me. I would expect the headspace issue to be even more pronounced with the more powerful cartridge. But...no criticism here, believe me. Here's a photo or two of the last sporting rifle I built for myself, was it 2 or maybe 3 years ago (?), and being age 80 it's likely the last I'll ever build. As you can see it's an L.E. numero uno. It remains a .303.

    Click image for larger version. 

Name:	IM006628.jpg 
Views:	20 
Size:	81.3 KB 
ID:	307181Click image for larger version. 

Name:	IM006626.jpg 
Views:	18 
Size:	72.8 KB 
ID:	307182 Click image for larger version. 

Name:	IM006621.jpg 
Views:	18 
Size:	84.5 KB 
ID:	307183


    DG

  15. #15
    Boolit Grand Master 303Guy's Avatar
    Join Date
    Oct 2008
    Location
    New Zealand
    Posts
    9,019
    That particular No4 was a trade in at a gun dealer and wasn't selling. The shop owner said was only worth about 40 quid or something like that. At that point is was wearing 308/303 target barrel with I think he said a 0.290 bore? A tighter than usual bore as used in target rifles anyway. by 308/303 I mean a 380 barrel chambered to 303 Brit. And it had fired thousands of rounds through that barrel plus it wore out the original barre, was FTR's and fitted with a 303 target barrel then rebarrelled with the 308 barrel.

    So they decided to do a destruction test to see just how strong the No4 really is. They rechambered it to 300 Win Mag and the action was strong enough but a crack on the bottom recoil lug had already formed and after 15 rounds fired, it broke off. 5 of those rounds were oiled to put maximum thrust on the bolt. Prior to the failure, there had been no bolt setback. They made a video of the process and that is what I saw. I'll see if I can find it.
    Rest In Peace My Son (01/06/1986 - 14/01/2014)

    ''Assume everything that moves is a human before identifying as otherwise''

  16. #16
    Boolit Grand Master 303Guy's Avatar
    Join Date
    Oct 2008
    Location
    New Zealand
    Posts
    9,019
    Found it! This is a must watch.

    https://www.youtube.com/watch?v=7bhWxFbYdyw
    Rest In Peace My Son (01/06/1986 - 14/01/2014)

    ''Assume everything that moves is a human before identifying as otherwise''

  17. #17
    Moderator


    Join Date
    Apr 2014
    Location
    Way up in the Cascades
    Posts
    6,771
    I did watch it! Hard to believe how much punishment the rifle took.

    DG

  18. #18
    Boolit Master
    Join Date
    Sep 2016
    Posts
    2,316
    The British did make a match or target rifle called the L39A1 and had a hammer forged barrel. And was a 308 as well. There was another one done up as a sniper also on the #4 action, but memory seems to recall it being a L42A1. Frank

  19. #19
    Boolit Buddy andrew375's Avatar
    Join Date
    Jul 2005
    Location
    uk
    Posts
    292
    Quote Originally Posted by samari46 View Post
    The British did make a match or target rifle called the L39A1 and had a hammer forged barrel. And was a 308 as well. There was another one done up as a sniper also on the #4 action, but memory seems to recall it being a L42A1. Frank
    They were marketed as the "Envoy " target rifle and the "Enforcer" for the military and police market.
    "Consciousness is a lie your brain tells you to make you think you know what you are doing." Professor Maria Goncalves.

    If liberty means anything at all, it means the right to tell people what they do not want to hear. George Orwell.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check