2nd Battalion163 Infantry and others: I. Rebone’s Artillery Duel, II. Japanese Mountain Guns on Biak

By Joe Rebone Sr. with Hargis Westerfield, Division Historian


I.      Rebone's Artillery Duel

On 12 June 1944 when 57 mm gunner Joe Rebone landed with 2nd Battalion Headquarters Company near Bosnek on Biak, he landed instantly in battle. He saw two Jap Zeros hit a destroyer, then get shot down by our Navy. Another Jap raid came that night. From the Bosnek-Parai road, we patrolled to the nearby low, dark-green ridges and found plenty of Jap supplies scattered around with plenty of heavy equipment.

By our fourth day on Biak, 15 June, Rebone was assigned to beach defense with his light 37 mm gun. He thought it a goofy idea - this beach defense with a gun ranging only 12,500 yards against Iong-range Jap Navy cannon, with a crew safe behind armor. We could not dig deep enough into the hard coral for any protection at all.

On 16 June, however, the 37 mm gun and crew that Rebone belonged to along with the other 2nd Battalion guns and crews were moved farther down the coast to fire inland. Already, we were supposed to fire inland to knock out a Jap field piece in those sinister, low-jungle, ridges before us.

     The position was poor, but living quarters were fine. The Air force had left behind an officer’s tent with comfortable canvas cots. A friend back in Supply had issued Rebone a new jungle suit, socks, and a towel. Closer to the beach there was a cool stream for bathing. But some mortar fire came from the Japanese ridges, and our gun crews had only hard coral to try to dig into.      
     Rebone's 37 mm gun was a graceful, low-profiled killer, with a barrel 82.5 inches long. It fired shells weighing 1.92 pounds (high explosive) or 1.6 pounds (armor piercing). At 1,000 yards, it could penetrate two inches of steel. Although too light for fighting thicker-armored European tanks, it could be effective in the Pacific war against lighter Japanese tanks. In the Sanananda Battle, it had also been useful to strip leaves and branches to flush snipers from their jungle cover.

At this time, Rebone did not realize how useful a little 37 mm gun could be on that coast below Ibdi Pocket and Bosnek. He did not know that our heavier 105s and 155s were needed to win the main Battle of Biak in the fight for Mokmer Strip.

On 15 June, S Company 163 Infantry suffered casualties from a mountain gun near Parai Defile. Near Rebone's position, G 163 and A Company 116 Engineers also received shellfire that destroyed a "G" mortar, killed two men and wounded six. It looked as if Jap Infantry would follow through with an attack, but there was no attack. Major Irving, 2 Battalion 163's Commanding Officer, alerted gun crews of our 37s to be on duty to fight the Japanese cannon throughout the daylight hours.

 In the dying light of late 19 June at about 1800, Rebone had one of 163 Infantry's memorable moments of the war. A Jap 70 mm gun opened fire. Taking shelter under a cot in his tent, Major Irving thought that he heard 12 distinct rounds impact from the Jap cannon. He phoned our 37 mm battery to open up.

      But Joe Rebone, with his assistant Dick Lund, had already crouched behind the 37 and tried to sight on the Jap target. (The sights of the other two 37 gun crews were masked by the trees of the rain forest.) The Sergeant in charge of the guns was too far away to help. He had to take cover from the Jap's shells.)

Rebone, with Lund at the breach of their little gun, first fired three armor-piercing shells of 1.6 pounds. Rebone hoped the shells would pierce the mountain gun's shield and kill the gunners or drive them away. Next, Rebone changed to a salvo of 1.92 high explosive shells.

In the brief silence that seemed to last forever, Rebone said afterwards that he chilled with fear. Would the Japanese gun crew depress their piece to fire down the path of the Yanks' own shells?
     Rebone and Lund still crouched behind their gun. They now fired more high explosive shells for effect. Final total of 37 mm rounds: three “APs" and 18 "HEs." Rebone believed that the last six rounds completed their victory. The Jap gun never returned fire.
According to 116 Engineer's Sergeant Ken Gwin, the Japanese gun was probably a 70 mm Infantry Howitzer, Model 92. The barrel was much shorter than that of the 37 mm gun. This 70 mm's barrel was just 28.5 inches compared to the 82.5-inch length of the 37 mm, but fired 8.3-pound high explosives.
     The defect was not in the gun, but in the way the Japanese used it. Instead of concentrating heavy fire in a four gun battery controlled by phone, firing simultaneously on a target, it was used like a sniper's rifle. If four of these guns had fired surprise shell fire, it could have wiped out the supply center of A Company 116 Engineers, and killed many men before our 37s could have gone into action.)

Japs fired only one mountain gun, and only one light 37 mm gun silenced it - manned by gunner Rebone with assistant gunner Lund.


ll. Notes on Japanese Mountain Guns on Biak

Our record of Rebone's duel raised questions about the Japanese mountain guns on Biak that are hard to answer. 'When and where were they used? What success did they have against our troops? Finally, how many guns did the Japs really have?

First notice of these guns appears in 163's Journal early on Biak, 7 June 1944. A message carne from Major Munkre's dump, which was probably near 3rd Battalion 163 Infantry. They were receiving fire from a ridge immediately north of Mokmer, and so far our field artillery fire had been ineffective against it. Eight days later, Captain O'Dell reported that 3rd Battalion 163 was taking field artillery shelling and asked if whether it was friendly but in error. Regimental G-3 (Operations) said that it was Japanese fire.

Not until 15 June, however, did several mountain guns probably go into action. By now, our 2nd Battalion 163 Infantry had arrived from the Toem-Wakde area and was positioned on the coast below the low, dark-green ridges that would be called Ibdi Pocket. The Jap guns above us seem to have been part of the Jap's 3rd Battalion 222 Infantry combat team assigned to help defend Ibdi Pocket.

Near Parai Defile, one mountain gun threw surprise fire into E Company 163 Infantry, which was farthest down the coast of all the 2nd Battalion 163 outfits. Ignoring E Company's forward perimeter on the ridges, the gun blasted five men playing poker while off duty. Being on solid rock, still they tried to save themselves by flattening on their faces. The gun killed Sergeant Frank Quam, wounded four more men: Pfc Theodore E Railsback, Pvt Harold E Appleton, Pfc Harold Metzger, and Sgt Arthur Morris. All were marked as seriously wounded. One was evacuated all the way back to Hollandia for hospital attention. E's Torgerson thought that a US 20 mm gun destroyed that Jap gun.

East of 163's E and B Companies, G Company 163 Infantry and A Company 116 Engineers also took mountain-gun shelling. In the last full light after supper just before sunset, projectiles impacted near G's command post on the flats. It drove the kitchen crew, weapons men, and others into any holes they could find. At first, Juster and Stalker returned fire with their 60 mm mortar. But they had to leave their mortar pit and shelter themselves behind a heap of steel pipes left by the Japs. A shell smashed their mortar. Kitchen man Northcutt was wounded in the groin.

On that same date, just after supper, a Jap 70 mm mountain gun shelled A Company 116 Engineers east of G Company. From the coral cliffs, Jap gunners made direct hits on two supply trucks. Two Engineers died (names unknown), and 13 got Purple Hearts for wounds that day. Wounded included Morris, Moore, Turosik, Williams, Maas, Kobeson, Devine, Roberts, Potscavage, and Alexander. As mentioned earlier, it was not until five days later that Rebone and Lund fired 21 rounds from their 37 mm to silence the Jap gun.

Major Irving of 2nd Battalion 163 Infantry said the Jap gun would fire 12 rounds, then safely hide behind an angle in an L- shaped cave until again ordered to fire.

Four days after A Company 116 Engineers took casualties, some G Company 163 Infantry men came under Jap mountain gun fire; Westerfield of G Company still vividly remembers this shootout. Although all of G's three rifle Platoons and Weapons Platoon now garrisoned on Ibdi ridges, it was Westerfield's time for a day's rest with a bath near G Company's rear echelon down on the flats.

When the gun fired, it caught me about mid-day, when I was luxuriating with soft Jap soap in the pool from a large freshwater spring near the beach. Then the gun seemed to snipe at me personally.

This scared man splashed out of the spring and took cover in a kind of cave. It was a coral ledge with razor sharp, pointed stalactites hanging down to menace my naked body. Crawling carefully, I took no cuts from the coral. The trajectory of the gun was so flat that the shells passed far over my head.

But from the beach where he had been hunting for cat-eye shells, Sergeant Schumacher came running. He was white all over his green fatigues from head to foot where he had groveled in moist, powdered coral.

Another story of a Japanese mountain gun came from Riley Maxwell of G Company 641 Tank Destroyer Battalion, later remained 98th Chemical Company. For about two weeks, D Company’s 4.2 rifled mortars fought this gun located on the ridge just before Parai Defile and past the west flank of 2nd Battalion 163. It might have been the same mountain gun that caused the death of one E 163 man and wounded four more on 15 June.

For about a fortnight, the Jap gun crew could zero in on 641 TD's bivouac, but our men could not spot the gun. About dark, it would fire 3-4 rounds and cease fire before our mortars could land useless fire somewhere near it. After it failed to shoot one night, 641 TD was recalled to Hollandia. The Biak Journal of 163 Infantry further complicates the questions already hard to answer about the Jap mountain guns. Several Journal entries confuse these guns with light infantry weapons. They even call the Japanese 37 millimeter guns mountain guns! Not until the final mop-up after the end of the fighting on Biak do we know of any Yanks who actually saw a mountain gun, or even the parts of one. After 22 August when 163 Infantry, our field artillery, and the Army Air Force wiped out Ibdi Pocket, three 75 mm guns, or their parts, were found in the debris.

These are all the available facts about three probable Jap mountain guns on Biak. On 15 June 1944, they had limited success against E Company 163 Infantry and A Company 116 Engineers killed three, wounded 17. But for no discoverable reasons were they used with only even minimum efficiency on Biak.

Just a few miles inland from the Bosnek-Mokmer Road, Colonel Kuzume's main force was fighting to keep us from seizing Mokmer Strip, the strategic objective of the whole US invasion. Entrenched in Ibdi Socket, the Japs could dominate our main road for reinforcements and supplies we needed to win Mokmer Strip.

Because the Japanese had no intention to surrender, they could have died gloriously in battle for the Emperor - in the heroic tradition of Bushido.


CREDIT: Most important is Joe Rebone's diary, 6 March 1944 through 12 December 1914, together with AT Platoon Leader 1st Lieutenant Charles Cardwell's "Recommendation of Award of Bronze Star." Information on operation of US and Jap guns is from Ian Hogg's Encyclopedia of Infantry Weapons of World War II (New York: Crown Publishers, 1977). Don Torgerson sent me his Diary of E Company 163, 9 June through 5 August 1944. Frank Turosik contributed a two-page letter of A Company 116 Engineers plus a list of Engineers' Awards of Purple Hearts on Biakin 1944. More on the Engineers came from Ken Gwin's History No. 208, From Port Moresby to Zamboanga, in the May 1991 Jungleer. I used also two of my histories from my Fighting Jungleers, Irving's Siege of Ibdi Pocket, (2nd Battalion 163 Infantry), and my own Ibdi Pocket and G Company. I also examined the 126-page "Journal" of 163 Infantry On Biak. A letter from D Company 98 Chemical Company by Riley Maxwell in the November 1991 Jungleer influenced me to make this study of Jap mountain guns on Biak.