Turci dobijaju nove haubice BORAN-105mm
Turkey gets new 105mm artillery: 17km-range, LRF, 6 rpm, 360° shots Citat: 105 mm towed howitzer BORAN will enter the inventory of the Turkish Armed Forces in August 2022, learned BulgarianMilitary.com, citing Turkish sources. In January 2022, at the test site in Konya Karapanar, the Turkish artillerymen carried out a series of tests, which completed the qualification of the weapon system and gave the green light to start serial production.
https://bulgarianmilitary.com/2022/06/29/turkey-ge.....360-shots/
Lici da je americka 105mm dzebana, a kod njega se granata stavi u cauru (nakon sto se iz caure izbace viskovi punjenja), pa se zajedno ubacuje.
Samo, 6/minutu je bolno sporo za tu klasu orudja.
Jako interesantan video, ko zna nemacki ( )o svajcarskom razvoju topa 155/47 KAWEST... Rekao bih da ce raketas uzivati .
Ukratko prevod na engleski pokupljen sa jednog drugog foruma:
Citat:Mr. Lanz of Lanz-Odermatt fame going through through some Artillery/Fortressartillery developements from 1950's to 1980's, mainly concentrating on the Swiss efforts which led to the M109 KAWEST in the 80's and the development of the last generation of Fortress guns, the 155mm L52 Bison. Also some interesting general info for those interested in general artillery developments.
Only in Swiss German. Rough translation below.
6:08 Overview of the Presentation
From 16:45 various destructive testing of the prototypes for the bustle charge magazine for the M109 KAWEST.
18:05 Test with only 2 charges in the magazine of a late prototype
19:20 Test with full magazine of a late protoype. Temperature in the fighting compartment increased to 40°C but no pressure increase. Final version had added internal divisor so that cookoff would be confined to a half magazine. (AFAIK the KAWEST is still the only SPG with seperate vented charges but current experience shows this should be a basic design requirement).
30:59 No significant differences between a gun mounted on SPG or fortress, but only small experimental sample.
31:45 best gun of Swiss Artillery inventory prior to introduction of Bison was watercooled 15cm TK 58 with 30km range and sustained fire capability of 24 rounds/minute
31:55 installation for the above, depth was about 50m.
35:00 Swiss trials of UK 105mm L118 Light Gun. Deemed too expensive, and apparently there was an existing decision to only accept 155 guns in the future. Doesn't go in on why then the trials took place at all. Decided to lengthen the barrels of existing howitzers to increase their range instead.
39:00 L39 barrel shortened to L30 155mm barrel on an existing 105 Hb carriage. Military didn't want any more towed guns.
43:07 Pz68 SPG variant w. 4 prototypes. Record range for it's time. However, very heavy at 45t, cartridge ammunition since it was adaptation of the above 15cm Tk58, cramped, expensive.
46:32 Mentions German trials of SPG on Leo1 chassis with 10 prototypes. Apparantly many of the same issues as above as well as unreliable. Needed 3 weeks to play through the standard 24 h NATO combat day. Follow on conclusion tank chassis are not suited for SPG conversion. Cost about a billion CHF equivalent.
47:30 Swiss were involved in early conception stages of PzHb2000 project. German project lead had reliability obsession, probably trauma from Leo1 project.
49:42 mentions they got a 12cm Rheinmetall tank gun a few years before Leo2 was selected and was used for various trials, but special concentration on making an autoloader. (Probably for the pending indigenous Nkpz project)
50:11 Destructive testing of the Centurion turret bunker with 155mm artillery, 120mm mortar and 105 tank gun fire.
51:45 Test with static mounted Maverick warhead with about .5m standoff. Blast blew the cement roof off and wrecked the gun but did not penetrate the turret (Bunker Cent turrets had massive add on frontal armour arrays)
54:34 1982, specifications for new Fortress gun, range at least 30km, ideally 40km. Caliber was not specified
55:28 settled on 155 because: ammo commonality with field forces, can be loaded by hand, focus of international research with pending precision and AT capability.
55:59 mathematical results for influence of caliber on range
59:12 longest possible barrel length that could be locally produced was 7.4m which worked out to L47 for a 155, this became basis for trials.
100:19 pressure tolerances of various ammunition. Swiss standard StG 66 being of older construction could only handle 3000bar due to narrow driving band (US M107 had same issue). The then new NATO L15/L17 was taken as reference round, it was 2-3 times more expensive than the StG 66. Follows a few slides i posted in the 105 vs 155 thread.
101:54 155mm fragments and penetration test of fragments vs Peraluman.
104:45 Impact comparison HE and DPICM
106:45 Increasing the range also means increasing the chamber volume. The US M109 L39 w. chamber volume of 19litres and 2800 bar, Vo 680m/s reaching about 18 Km.
107:40 US trials to increase range involved a bigger charge originating from M198 with 4300 bar and Vo 830m/s mated with the existing L39 barrel. This turned out to not be doable. Too much damage, especially the higher gas pressure led to damage of of the muzzle break.->Taylor Report. The US dealt with this by redesigning another L39 barrel assemby that could deal with the higher gas pressures, but they also needed new ammunition (L15/17) as the M107 couldn't deal with them->Paladin.
109:17 He had access to the report and for him the straight forward of dealing with the added gas pressure was to lengthen the barrel.
110:25 K+W proposal for M109 KAWEST, L47, 3500 bar so still compatible with StG66, Vo 830m/s, with added charge 4300 bar, Vo 900+m/s with new ammunition (the cannister rounds). Fairly cheap since backwards compatible with existing ammunition.
112:07 in addition to the above work was going on for the new Bison Fortress 155. They saw the work of GC Bull, but unlike Bull didn't want to increase the existing L39 chamber volume to keep commonality with the existing ammunition.
113:28 The two concepts for Bison, "Inter" was chosen to keep commonality with exisiting ammunition but they did some trials with with the concept "Mille" which would mean pushing for Vo 1000 m/s but this was deemed both expensive and risky, as nobody was trialing shells for those speeds and they would need to develop completely new charges.
114:28 "Mille" trial vehicle with L52 and 26 liter chamber, this reached an average Vo of 1001 m/s.
115:31 intermediate Bison and KAWEST proposal. L47 with increased chamber volume to 21 (from 19 liters) which was the same as a fully eroded L39 barrel. Near complete elimination of barrel errosion with new charge additives and a fully chromed barrel. They adjusted the twist rate and also groove profile, the latter to allow better chroming (119:54). With max charge and the new NATO ammunition it allowed shooting past 40km with normal shells while keeping backward compatability at lower charges.
The L47 limitation was industrial, since the the crane height at the barrel manufacturer didn't allow all production steps for a longer barrel. However K+W Thun did have the crane height and could do the work after the barrel was bored. This allowed going to L52, which was done for Bison.
118:56 The inability of the chroming factory to chrome 8 meter barrels threatened to delay the trials. So they made a some what longer barrel, cut it, had the parts chromed separately and then welded them together.
119:54 Original groove profile was too steep, so wall angle was shallowed to enable better chroming.
120:49 Twist rate was a big discussion. They made experiments with progessive twist which seemed promising, including pulling through shells to see how the driving bands interacted with it. This seemed a possible solution but they decided to stick with a constant twist.
121:24 New barrels need about 50 rounds to settle. With chromed barrels this is no longer possible. The following part I didn't quite get. They made an insert to prevent the settling in effect. Not sure if this means the geometry changes made the settling unnecessary.
122:56 provisional Bison L52 trajectory chart
123:40 barrel fatigue life, apparently the US at some point had 3 accidents with nearly new 175mm barrels, which led to generally more attention being paid to barrel fatigue issues.
126:00 empirical 50% dispersion spread of fires at various ranges out to 40km, hence need for intelligent ammunition for effective fire
From 127:30 to 130:30 short film in barely audible English on Bison/Fortress guns. The autoloading mechanism used for Bison was first trialled in M109's, though the KAWEST ended up using a flick rammer in the end. Bison could do 5 shots in 25 seconds.
130:58 overview of the Bison - KAWEST project links
132:09 overview of munitions used in the trials.
133.15 instead of a watershroud for the barrel as in the 15cm Tk58 they decided for simply pumping water into the barrel directly.
133:51 casemate installation. The small blocks were reactive armour modules.
135:04 test of Maverick warhead against armour array, didn't penetrate
136:16 KAWEST improvements
- 155mm L47 chromed
- new additional charges
- flick rammer
- navigation system, self laying
- new electrical system to handle the extra equipment
- vented bustle rack for charges
- fire surpression system
- Nightvision for commander and driver
137:00 wrap up. Where has the been the advancement?
- since 1935 litte advancement in muzzle speed with the max Vo still around 930 m/s.
- advances in barrel technology mainly in terms of lighter weight, improved barrel life, safety and build quality
- main technical advancement has been in the ammunition
)o svajcarskom razvoju topa 155/47 KAWEST... Rekao bih da ce raketas uzivati 
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