Article written by Mr. Daniel O”Dea in “AUSTRALIAN & NEW ZEALAND HANDGUN” issue 7, 2009
DPM Systems” recoil reducing guide rods
Among the 1950 exhibitors who displayed at the 2008 US SHOT Show was DPM Systems Technologies Ltd. a company that specialises in two products designed to reduce felt recoil in hand-guns. More specifically, Greek inventor Dimitrios Mantas of DPM Systems has come up with both a mechanical and a magneto-mechanical answer to reducing recoil.
In brief, the magneto-mechanical system clips onto the accessory rail of compatible pistols and uses magnetic force to momentarily delay the slide”s rearward movement on firing. The theory on this one is that this momentary delay maximizes the excape of gas from the muzzle and consequently, has the slide moving back more gently and transmitting less kinetic energy upon the frame.
The second, mechanical system uses a replacement guide rod that incorporates a captive spring unit, as well as a mainspring for a total of three springs, the theory behind this one is the patented captive spring system creates a variable spring tension, which increases proportionately as the slide goes rearward, decreasing as it runs forward and then increases slightly again as the slide and barrel lock into battery, this unit is purported to act as a slide buffer, reduce slide slap and basically better manages the recoil through the pistol”s frame.
The DPM Systems website claims the system just about “cure”s all that ails ya!” with respect to recoil, with a long list including significant recoil reduction, better control and greater accuracy, slide protection, elimination of jams, better double-tap concentration, improved firing speed, faster follow-up shots, frame protection and all requiring no modification. Talking to US distributor Steven Paganis, he passionately extolled the virtues of fitting the system and showed me graphs and even a video to support the claims, despite all of this, I”ve got to admit I was still a little skeptical when Steve offered me a sample to review.
Over the next few months, I gave some consideration as to how I could conduct some quantitive testing that would prove or disprove the claims. The problem was that the perception of recoil is very much a personal thing. Indeed, what one person may consider to be mild recoil, another person may have problems handling. A person, who might be conditioned to heavy recoil or just possesses superior gun control built from years of experience, may be less able to distinguish a quantifiable difference than someone who might be recoil-sensitive.
I decided the best way to go would be to gather together some willing and able guinea-pigs and conduct a “blind” test. Now, of course, what I mean by a blind test has nothing to do with them wearing a blindfold; rather I would get my volunteers t o test fire the system without actually knowing what the purpose of the test was. To action my plan, apart from the volunteers, I would need two identical firearms, some heavy loads and an appropriate venue.
The DPM guide rod system I was given was for a Smith & Wesson M&P Series Pistol, which just happens to be what I primarily use for IPSC Production Division. After a quick call to Stuart Collibee from Grycol International, I had a second identical pistol for the test. Tony Abela from Sydney”s Horsley Park Gun Shop generously stumped up some ammunition for the experiment, providing me with 200 rounds of Speer 147-grain Gold Dot in 9mm.
With everything in hand, as the range safety officer (RSO) on duty for our Tuesday night IPSC shoot at the SSAA St Marys Pistol Club in New South Wales, I showed up early to set up the match, which was to include one special stage. I set up a table with two standard IPSC paper targets 10m downrange. On the table directly in front of each target lay a Smith & Wesson M&P 9mm pistol and a magazine with five rounds of ammunition. One gun was fitted with the system and one was standard. Only my able assistant and fellow RSO Peter Hopkins and I would know which one was which – the rest of the guys would have no idea and had no knowledge of what was on for the night until they showed up.
I”ve never met a shooter yet who wasn”t happy about getting some free trigger time behind a new gun shooting someone else”s ammo, so naturally, everyone was more than happy to participate. The range briefing was simple: from a loaded gun-down position, on the start signal, the shooter would engage the first target five rounds Rapid Fire. The gun would then be cleared and paced back down on the table. The shooter would move over to the next gun and repeat the stage. When finished, the targets would be scored and assessed for round dispersion, while the shooter would be taken aside quietly and asked whether they had noticed any difference between the two firearms.
At the completion of the test, we came up with the following conclusions. Five out of eight shooters (62,5 per cent) shot a tighter group with the system fitted. One (12,5 per cent) shot the same group size, with the remaining two shooters (25 per cent) favouring the standard gun. Half of the group could not distinguish any difference between the two guns; however, the other half all identified the gun fitted with the system as being easier to fire. Three shooters specifically referred to the DPM-equipped gun as “flipping less” under recoil. Other comments included that the sight recovery was quicker and that the gun was more comfortable to shoot.
Now remember, none of the shooters were aware of what they were testing and the questions asked and comments received were held in confidence between participants until the end of the test. As such, it was interesting to note some near-identical comments with respect to how the gun behaved under recoil.
I guess even firing hot factory ammo, the 9mm is far from being a beast to handle recoil-wise. However, in consideration of the firearms available to shooters in Australia, I felt it was the most appropriate caliber to test. Likewise, the Smith & Wesson M&P has great ergonomics and handles recoil well in its own right. All taken into consideration, the test clearly indicated that most shooters shot better with the system than without and more than half indicated a marked change in the way the DPM-equipped gun behaved under recoil.
Personally, I” m convinced it does work. I shot near-identical times between the two targets with only four one-hundredth of the second difference. My group was tighter with the DPM-equipped gun and I felt the gun recovered quicker with it than without. I also felt the sight recovery was faster. It stands to reason that by virtue of how the system works with varying spring tension that it would buffer the slide somewhat and transfer less kinetic energy through the frame, so I believe this claim could also be substantiated.
I didn”t get to test the magneto-mechanical system, but I would be interested in seeing the effect of having both fitted in combined operation, as recommended by the manufacturer for maximum effect.
It would also be interesting to give the system a run in a higher-caliber handgun such as a 40 S&W or a 45 ACP and in the interest of science, I might just get around to that one day.
The DPM Systems as tested might not be the definitive answer on recoil for everyone, but I do believe it does do enough to make it worth exploring for those who may be recoil-sensitive or just want every bit of help with gun control they can get. It is available for most modern pistol variants including CZ, Glock, Sig, HS2000, Beretta and of course, the Smith & Wesson M&P. It should be noted that some pistol disciplines might not allow the changing of the guide rod in their rules, so check first if you are buying one specifically for competition.
I”m unaware of any current distributor for this product in Australia. However, the US distributor Steven Paganis who gave me the sample offers direct web sales at www.theshootersbox.com with the mechanical system as tested starting at $US75. Information on this products can also be found at the DPM Systems Technologies website at www.dpmsystems.com.
Daniel O”Dea would like to thank Tony Abela from Horsley Park Gun Shop for his generous support with the ammunition and Stuart Collibee from Grycol International for supplying the second gun.