Welcome to the Inert Ordnance Collectors.
Page 1 of 3 123 LastLast
Results 1 to 10 of 28
  1. #1
    Premium Member
    Join Date
    Jul 2008
    Location
    United Kingdom
    Posts
    4,438
    Thanks
    1,473
    Thanked 1,513 Times in 646 Posts

    Squeezebores from other countries

    There's a good thread running about German squeezebores so I thought it was time to try and consolidate photos I've posted in various threads into one post in the hope others could share photos of their squeezebores. I use the term fairly loosely, in the UK they were referred to as littlejohns, elsewhere cone bore, the ones I'm showing are projectiles that get squeezed as the go down the barrel and exit with a far smaller diameter than they started.........so at the risk of boring you guys here goes, I hope you enjoy the photos, oh and if anyone has any spares in their collection I'd be glad to buy/swap................


    20mm mystery.
    This came from a Swedish collection, I know nothing about it but am of the opinion its real. Its made out of different parts with the flanges being put on separately.
    Anyone any ideas?
    017.jpg

    37 x 222
    The photos show a 37 x 222 unfired projectile next to a fired one next to a fired sectioned one.
    007.jpg

    40mm (2 pounder)
    Two 2 pounder mark 2 littlejohns, one in section and one complete. These are the most common types out there (they're still hard to find).
    014.jpg

    40mm (2 pounder) and 40mm Bofors littlejohn. Both fitted with Mk 1 projectiles.
    If it wasn't for the provenance of the Bofors I'd have said it was a made up round BUT a Bofors littlejohn was made and tested. Shown next to a mk 1 two pounder littlejohn for scale.
    015.jpg

    Swiss 47mm.
    I don't have any more information on this one, any help appreciated.
    016.jpg

    Jones and Lamson 57mm (USA).
    012.jpg

    6 pounder 6cwt
    008.jpg

    17 pounder
    I think this is a 17 pounder flat head proof littlejohn. Its been fired without the attachment. I know of 1 other identical one in another collection.
    010.jpg

    All together
    A group photo to show the scale of the different rounds.
    018.jpg

    ALL re INERT.

    Dave.
    Attached Images Attached Images

  2. The Following 10 Users Say Thank You to SG500 For This Useful Post:

    apfsds (21st April 2013), doppz92 (18th April 2019), fert (28th December 2011), Fjordhouse (27th December 2011), Gau 8 (27th December 2011), proditto (9th November 2013), rcaf53 (28th December 2011), RichardB (28th December 2011), Weasel (10th May 2014), wichitaslumlord (18th April 2019)

  3. #2
    Premium Member
    Join Date
    Mar 2009
    Location
    U.S.
    Posts
    4,279
    Thanks
    568
    Thanked 1,144 Times in 659 Posts
    Really nice stuff Dave!

    Hey, I have a question. What is the exact definition of squeeze bore? The reason I ask, is because recently US-subs posted a photo of a 3 inch 70 projo, that is a probert design. So are the 3.7 inch probert and 3 inch 70 cal probert projectiles considered a squeeze bore projos?
    ___HAZ/
    _____/ORD Hazardous Ordnance Recognition
    ________Saving Lives Through Education

  4. #3
    Premium Member
    Join Date
    Jul 2008
    Location
    United Kingdom
    Posts
    4,438
    Thanks
    1,473
    Thanked 1,513 Times in 646 Posts
    Quote Originally Posted by HAZORD View Post
    Really nice stuff Dave!

    Hey, I have a question. What is the exact definition of squeeze bore? The reason I ask, is because recently US-subs posted a photo of a 3 inch 70 projo, that is a probert design. So are the 3.7 inch probert and 3 inch 70 cal probert projectiles considered a squeeze bore projos?
    Thanks John.
    According to Ian Hogg in his book "The Illustrated Encyclopedia of Ammunition" a squeezebore is a "type of gun in which the diameter of the barrel is suddenly reduced at some point along the bore so that the diameter of the projectile is similarly reduced". In the case of German ammunition the barrel reduced along its length so it was in effect a cone hence the wording "cone bore", in the case of most if not all of the ones shown on this thread the shell was fired along the barrel at full bore and then passed through a non rifled adaptor screwed to the end of the barrel, in the case of the British ones it was the littlejohn adaptor, the adaptor squeezed the flanges into the recessed parts of the body so the projectile emerged with no clear rifling on it.
    With the Probert driving bands shown on US-subs recent thread they work in a different way and the bore of the gun does not reduce along its length. Ian Hogg in his book "British and American Artillery of World War 2" describes the rifling on the 3.7 inch mk 6 as follows: "Since a high velocity was demanded a new system of rifling was proposed. Known as "RD" (Research department) Rifling, it was designed by Colonel C.O.C, Probert of that Department and it worked in conjunction with a specially designed shell. The rifling commenced at zero depth and the lands gradually assumed their full height at just over four inches from the commencement of rifling. Towards the muzzle the groove depth gradually reduced until at 11 inches from the muzzle the bottom of the grooves had come up to meet the top of the lands and the gun was a smooth bore. The shell was fitted with a high efficiency driving band and twin centring bands at the shoulder. These had the effect of dividing the torsional stress of spinning more evenly along the length of the shell and centring the projectile more prefectly on the axis of the gun barrel. As the rifling grooves decreased, the copper of the driving and centring bands was squeezed into the cannelures in the shell body, and on leaving the muxxle these coppper bands which normally protruded into the air stream and degraded the shells flight were smoothed flush with the shell wall to permit the unbroken air flow over the shell which helped to sustain the velocity."
    So to answer your question, its all a bit grey, both systems squeeze the projectile, I would interpret it that the flanged squeezebores reduce in diameter significantly as they pass down the barrel which is itself coned at come point, with the Probert system the actual projectile is not reducing in diameter, only the copper driving bands.
    Dave.

  5. #4
    Senior Member
    Join Date
    Jun 2007
    Location
    Germany
    Posts
    2,627
    Thanks
    32
    Thanked 610 Times in 400 Posts
    Dave, thanks a lot for the awesome images!

  6. #5
    Senior Member
    Join Date
    Jul 2008
    Location
    spain
    Posts
    334
    Thanks
    65
    Thanked 88 Times in 67 Posts
    These shells are there?, jejej
    you wonder, here in Spain hurts not come ...
    Happy new year

  7. #6
    Premium Member
    Join Date
    Jul 2008
    Location
    United Kingdom
    Posts
    4,438
    Thanks
    1,473
    Thanked 1,513 Times in 646 Posts
    Thanks for the feedback guys. Hasag I am not sure what you are trying to say, sorry.

    Dave.

  8. #7
    Senior Member
    Join Date
    Jul 2008
    Location
    spain
    Posts
    334
    Thanks
    65
    Thanked 88 Times in 67 Posts
    I meant that these projectiles are fantastic
    That here in Spain never saw them.
    What luck you have.
    a greeting
    and Happy New Year

  9. #8
    Premium Member
    Join Date
    Jul 2008
    Location
    United Kingdom
    Posts
    4,438
    Thanks
    1,473
    Thanked 1,513 Times in 646 Posts
    Quote Originally Posted by hasag View Post
    I meant that these projectiles are fantastic
    That here in Spain never saw them.
    What luck you have.
    a greeting
    and Happy New Year
    Thank you, I understand now.
    Dave.

  10. #9
    Premium Member
    Join Date
    Jul 2008
    Location
    United Kingdom
    Posts
    4,438
    Thanks
    1,473
    Thanked 1,513 Times in 646 Posts
    Hi guys, help me out here please, does anyone else have photos of similar rounds they can post?
    Has anyone got the super elusive 6pr 7cwt littlejohn or even some of the small calibre rounds that were made?
    Dave.

  11. #10
    Premium Member
    Join Date
    Jan 2008
    Location
    Oregon, U.S.A.
    Posts
    315
    Thanks
    124
    Thanked 247 Times in 94 Posts
    Dave,

    This should be some useful information if you haven't seen it before. I borrowed a copy of a report on U.S. Development of squeezebore and HVAP ammunition in WWII from a friend recently. I finally scanned the images tonight and added a few here. All of the images can be seen here:

    http://imageevent.com/ricklarson/usgerlichdevelopment

    I hadn't realized that the U.S. Army began such development before our entry in WWII, based on a German 28/20mm gun and ammunition captured at Halfaya Pass in 1941. Our first gun was a 28/20 T5 barrel assembly fitted to a 37mm M4 gun carriage, starting with sketches made in June, 1941. The cartridge case was the T2, a copy of the German case, and 1098 were produced at Frankford Arsenal by March, 1942. The projectile was designated T6.

    When the development moved up to 37mm, the next round was designated "Shot, H.V.A.P. 37/28mm T25". It appears the engineers followed the British Little John work with a tapered muzzle attachment fitted to a straight bore cannon. There was also a 57/40mm project and it appears all of the later WWII high velocity experiments moved away from taper bores in favor of H.V.A.P arrowhead projectiles in straight bores. Hope this is useful for you.

    RickGerlich%20Report%207.jpgGerlich%20Report%205.jpgGerlich%20Report%208.jpgGerlich%20Report%20010.jpgGerlich%20Report%20012.jpgGerlich%20Report%20016.jpg

  12. The Following 4 Users Say Thank You to ordnance For This Useful Post:

    apfsds (21st April 2013), bdgreen (3rd January 2012), doppz92 (20th April 2019), SG500 (30th December 2011)

 

 
Page 1 of 3 123 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Back to top