View Full Version : Ground Mum's on Arisaka Rifles

January 11, 2008, 10:26 AM
The Arisaka has become a collectable rifle. Back in the 60’s, and 70’s, the shooting community did not have a high opinion of the Arisaka rifle. This was mainly due to the prejudices of the WWII generation who thought poorly of the quality of Japanese products, and they heard stories of junk "cast iron” Japanese rifles.

Another problem was that the Arisaka was difficult to customize and Norma ammunition cost almost as much as the rifle.

My Dear Old Dad brought back two Arisaka rifles directly from a collection location in the middle of Tokyo bay. This was in Feb 1946. We had required the Japanese to disarm and turn their weapons to Coalition authorities. Both the rifles had ground Mum’s. When I asked him about the grind marks, he said the Japanese had ground off the crests. So I always assumed that crest grinding meant a collected weapon, and that the crests were ground off by the Japanese.

Yesterday I was talking to one of our last Pacific War veterans, Sammy. Sammy is a leading member of our gun club, and he was in the Navy as a communications guy. His job was to relay messages from the ground commanders to the invasion Command ship. He was sent second wave on Iwo Jima and Okinawa. If you know anything about the survival rate of the early waves, you know he was lucky to survive. And he was in the thick of it. Sammy still will not volunteer information about his experiences, except to say the real heroes are still on the islands and that we lost a lot of good men.

I mentioned to Sammy that I saw at the range a Japanese Paratrooper rifle, and that it had an unground crest, and asked him if he had ever seen one. Sammy said he had never seen one, and he said he was glad never to have met a Japanese Paratrooper. As an afterthought, he said, “how did that rifle get in with an unground crest?”.

So I followed up. Sammy had brought back five Arisaka rifles, in his duffle bag. The muzzles just stuck out of the bag, and he tied them together with real heavy rope. He verified, that these were picked up by him on the battlefield, near or directly from dead Japanese. So these were not “turn in rifles”, and they had the crests on them.

However, when Sammy was returning home and came off the ship, everyone went through out processing in San Diego. At outprocessing, the US military authorities went through everyone’s gear, and would not let him bring his rifles in until the crests were ground. I assume there was a bench grinder nearby and those with rifles waited in line to have the crests ground. (I also assume there was a pile of Grenades, tank mines, and mortar shells that were going to EOD!). When I asked Sammy why the US authorities were grinding the crests, he said “we had an agreement with the Japanese”. Without a doubt, that was what he was told.

From all the sources I have read, a ground crest meant a turned in rifle, unground meant a captured rifle. But there must be a large subset of captured rifles which were ground by US authorities on US soil, after the Surrender of Japan.

January 11, 2008, 10:38 AM
you can still obtain the arisaka's with unground mums. I have 2 in my safe and I see them all the time on gunbroker. Unfortunately there are a lot more gound mum guns though :mad:

January 11, 2008, 10:48 AM
I had an unground one that was brought back by a serviceman from Iwo Jima. The stock was pretty bruised up but the metal was good. Unfortunately it was stolen.

James K
January 11, 2008, 03:09 PM
All I can say is that the story is interesting. No disrespect to your friend, but it was all a long time ago.

I have even heard that WWII vets told people that Japanese troops carried grinders around with them and ground the "mums" off before engaging in Banzai charges. Also that the Marines carried grinders to grind the "mums" off captured rifles because of some "deal" with the Japanese. ("To Japanese Commander: Please to not attack Marines right now as too busy grinding on rifles to repulse attack. Thank you. Signed, U.S. Marine Corps.")

IMHO, your first understanding is correct.

FWIW, I have also heard from WWII vets that the Japanese couldn't shoot straight because their eyes were slanted, that the 6.5 had no more power than a .22 Short, that Japanese rifles blew up all the time, that Japanese optics were trash (they sure learned in a hurry), that the Zero fighter was made of tin foil, that Japanese ships could be sunk with one shot from a Springfield, and on and on. Of course, some of those vets had been no nearer Pacific combat than San Diego, California, but they were vets, so who am I to argue with such experts.


January 11, 2008, 04:03 PM
Mine has a ground mum but it still shoots great. I had an older model rifle with the mum intact once. A 6.5MM type. The outsides of the gun were super excellent condition but the bore was a sewer pipe, unsalvageable in any sense. So maybe that corresponds to the legend I heard about them peeing in the barrels of guns so that when captured they would be rusted up? :) Remember the military is the countries largest organized rumor mill.

April 6, 2009, 04:24 PM
My grandfather was in the USN durring world war 2. After his death a few years back and my grandmothers last september we were granted permission via the wills to search and take what my family wanted. During my search i saw what looked to be the barrel of a ww2 bolt action rifle. I picked it up and immediately noticed the japanese characters signaling an original type 38 or arisaka rifle. the only problem is that the stock of the gun was missing. No markings on the original barrel, or firing mechanism have been taken off, does this mean i have an unground arisaka?

April 6, 2009, 04:43 PM
The "mum" (actually a chrysanthemum, but spelling mum is so much easier) was simply a mark signifying that the rifle was Imperial property, and the Japanese felt that surrendering a rifle bearing that mark showed "disrepect" to their "Emperor"; therefore, rifles which were surrendered as part of an agreement were normally "demilled" by having the mums ground off. Here's a picture of an unground "mum":


April 6, 2009, 05:04 PM
I have an un-ground carbine.

April 7, 2009, 11:56 AM
The "mum" (actually a chrysanthemum, but spelling mum is so much easier) was simply a mark signifying that the rifle was Imperial property, and the Japanese felt that surrendering a rifle bearing that mark showed "disrepect" to their "Emperor"; therefore, rifles which were surrendered as part of an agreement were normally "demilled" by having the mums ground off.

Saved me the time of typing that up, thanks! :) Saving face was and is in-grained into many cultures

April 7, 2009, 12:14 PM
My uncle brought one back as well and he too was in the Navy. The Mum was still present but I don't think he ever saw any ground combat or at least he never mentioned any. Perhaps those "Deck Apes" had access to some of these rifles. Two weeks ago, at a local gun show, I saw one that still had the original Mono-Pod, Sling and Mud-guard. Now that is rare !! He had the bayonet as well and like many, the hook had been cut off. When I noted this to him, he was not aware that it ever came with one or that the bore was chromed lined. The older ones were very good shooters.

Be Safe !!!

April 7, 2009, 12:53 PM
such children:they was much trading going on alot of troops that were not in combate traded for articals and so rifles captured went home.the grinding occured after japans surrender.and some officers were gun ho on regulations and others werent.Its true som guns were cast and dangerous,BUT that was because they were not made to shoot bullets but blanks I have had them,also one that I had, I have never seen mentioned and that is 7.7 cast receiver that the bolt entered the barrel and locked.I have 5, 7.7 and 2, 6.5.
and the ammo is corrosive so a gun not cleaned,will rust.the 7.7 is cromed the 6.5 was not.and you can make it from 30/06.and I would hazard that norma does that.their cases bulge more than 06 does. grafs has 6.5 brass.:rolleyes:

James K
April 8, 2009, 02:45 PM
The Japanese, like every other nation in WWII, used ammunition with corrosve primers. The Type 99 (7.7) had chrome plated barrel bores so they didn't rust, but with the Type 38 (6.5) there was no need for anyone to do anything to the barrel to make it rust except to leave it uncleaned for a day or so.

The Navy guys got a lot of souvenirs simply because they had a place to put them. In spite of wondrous stories, not many troops captured rifles in combat and then carried them around for a year or more until the war ended. An infantryman has plenty of his own gear to carry without toting rifles, machineguns, helmets, etc. as souvenirs. (Pistols were another story; easy to carry, many were brought home by the men who captured them.)

There was plenty of trade between Marines/soldiers and the Navy. The sailors had money and access to abundant food and other supplies. The ground pounders had souvenirs up the wazoo. The result was to be expected.

The oddest souvenir I know of was brought back by a sailor on a destroyer. It was a 37mm Japanese tank gun. The thing was about 8 feet long and darned heavy. I asked the guy how in heck he managed to get it back. He told me that he just stood it in a corner of the engine room and painted it gray. The only comment he got on it was from an officer who told him to clean "the steam pipe."


April 8, 2009, 03:30 PM
I have an original Type 38 with unground mums, bayonet with hook intact and the original rattling mud cover which I'm told is quite rare. On top of that, my rifle has initials carved in the stock by the Emperor himself!!

O.K., I made up the last part but everything else is true. My rifle has a good bore and is a darn good shooter. I've actually used it ground hog hunting with pretty good success.

April 11, 2009, 12:42 PM
I have a type I, no grinding anywhere. Came from my Grandfathers estate, no one in the family knows where he got it. He was staioned in Japan in the USAF, but they thing he may have picked it up an an aution or something.