I have had both and EASILY prefer the Ratmandu. ..... Although I don't know that I would say the two knives are really that comparable.
You might think that with the M6 having a 6" blade and the RMD having a 5.25" blade and if you have only seen pictures that the two knives are probably very comparable. But, there is a huge difference in weight, feel and balance.
The M6 weighs 16.5 ounces and feels very heavy and thick in the handle for a knife with a 6" blade. The height of the handle is fairly significant compared to the RMD or any other comparable length knife. The M6 is VERY stout and very capable of extreme heavy duty use. Some may want this. I feel it is over-kill and weighs too much for a knife with only a 6" blade.
The handle of the M6 isn't uncomfortable. I wear XL sized gloves and I could say the M6 handle is comfortable. The general shape of the M6 and the RMD handles are very similar, but the M6 has a taller and bulkier handle. The RMD just ultimately feels better. The RMD is not too smaller, is lighter and offers better feel, balance and weight which I prefer over the overly heavy handled M6. Aside from mudder grips, the RMD has one of the best if not best handles ever released from Swamp Rat.
The RMD weighs about 10 ounces. Which is actually still fairly stout and heavy compared to most comparable length knives. But, it is substantially lighter than the M6.
For comparison:
Ratmandu (micarta)....= 10.0 ounces; .190" thick; 5.3125" blade; 10.5" oal
DM..........................= 9.0 ounces; .268" thick; 5.25" blade; 9.75" oal
The DM (Scrap Yard - Dumpster Mutt) has a MONSTER thick blade and still weighs less than the RMD.
To me, the M6 is a very capable knife, but over built, overly heavy, and not enough blade length for the weight. I think there are better choices for a knife of comparable blade length that weigh less or comparable weight that have more blade and can chop and batton better.
Conversely, I feel the RMD is a classic and one of the best knives of it's size made - period!
There are a lot of fans of the M6 though and I acknowledge that personal preference and personal style of use are significant factors.
If you want a medium length knife with a chunky and heavy feel and extreme duty ability, the M6 might be for you.
To me, the RMD is a great all-around size and feel and PLENTY heavy duty enough. The RMD is a CLASSIC!
About the only way to improve the RMD is satin finish (IMO) and a little more convexing and sharpening of the edge.
I would personally prefer the RMD actually be a tad lighter in the handle, but most people probably won't complain about the RMD's handle weight at all.
I would still think my Concept ideas would be nice to see though!
See:
http://www.swampratknifeworks.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=10;t=005684#000001
The little bit of extra length in the M6 will aid in battoning a "little" bit, but not a whole lot better than the RMD. They can both be battoned.
The whole lot of extra weight in the M6 will aid in chopping for the M6. But, I don't feel a 6" blade is great for chopping in any event.
If you want a chopper, get the Chopweiler with a significantly longer and better chopping ability and with only about 3 more ounces or one of the many other great options from Swamp Rat or Scrap Yard with a longer blade. I think the Yard Guard from Scrap Yard is a better all around use than the M6, better feel and balance and weighs the same, but with 1.25" longer blade.
And of course the famous Camp Tramp if you can find one. The Camp Tramp weighs noticably less than the M6 with same thickness and significantly more blade length. The Camp Tramp pretty well blows away the M6 in my book.
The S6 from Scrap Yard has pretty much the same blade as the M6, but weighs 12.7 ounces has better, feel and better balance than the M6.
For a 6" bladed knife, I likely prefer SR-101 over SR-77. But.....
I think the M6 would have been a great knife if Swamp Rat still used Res-C. A lighter handle woud have changed the dynamics of the M6 quite a bit.
Instead, the option is a S6 from Scrap Yard with SR-77. Still a good knife!
Not including the many Busse offerings and just looking at Swamp Rat and Scrap Yard offerings, I feel the best single all-around jack of all trade knives go to:
Light weight/smaller: Swamp Rat - Bog Dog
Middle-weight - Swamp Rat RMD
Slightly heavier larger - Scrap Yard - S6
I tend to lean more towards a two knife combo, in which case for a smaller knife, I would chose one of these great options:
SS4
HRLM
Combined with:
Camp Tramp
Chopweiler
Yard Guard
-----------------
Camp Tramp............= 14.5 ounces; .235" thick; 7.325" blade; 12.5" oal
Yard Guard..............= 16.0 ounces; .277" thick; 7.25" blade; 12.4" oal
M6..........................= 16.2 ounces; .235" thick; 6" blade; 11.68" oal
Scrapper 6 LE...........= 12.7 ounces; .268" thick; 6.25" blade; 11.44" oal
Ratmandu (micarta)....= 10.0 ounces; .190" thick; 5.3125" blade; 10.5" oal
HRLM.......................= 9.0 ounces; .190" thick; 4.13" blade; 9.3" oal
Howler (Res-C)..........= 6.0 ounces; .188" thick; 4.5" blade; 9" oal
SS4........................= 5.5 ounces; .200" thick ; 4.25" blade; 9" oal
Bog Dog..................= 5.0 ounces; .140" thick ; 4.75" blade; 9.56" oal
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