Very frequently I see guys searching for tight chambers and actions that are glass smooth. This may be fine if you only shoot from a bench in the sunshine. These "match" rifles often suffer when the skies turn gray, the temp goes sub-zero or the shooter has to crawl through the mud.
After the Oregon Sniper Challenge I was reminded of this fact. During most of the match I was either in my "bubble" or BS'ing with other shooters off the line. I didn't do a lot of spectating as to how other competitors were shooting. That's just not my style unless someone needs help or it's a personal friend on the line. The night after the Challenge wrapped up, my host and match director Steve Huisman asked me about the numbers of problems he had seen on the line. He recounted seeing quite a few shooters pounding on their bolt handles to open or close their actions. This was during one of numerous downpours that we experienced in the lovely Oregon outdoors.
I thought about it for a few minutes and then pondered the times that I was on the line and the shooters that I did watch. I realized that most of the shooters that I watched were either shooting factory rifles or were professional LE Snipers. None of those had any issues. That's not to say that duty guns don't have issues. At a recent seminar I attended we discussed the number of issues that duty rifles can experience when improperly maintained or modified. Factory sporting rifles generally have extra tolerances built in due to the mass production process. Fitting is done where fitting is required. It's left alone where it's not required. On some "match" rifles, fitting is done because the customer expects a tight fit. Tight equals accurate....right? On rifles intended for military or LE Snipers an experienced smith will allow tolerance for dirt, grit, water and ice. The action may feel a little "sloppy" but they still lock up tight. Now on to the core of our problem....
The issues that were really discussed were the hard bolt closing and hard bolt lift. Hard bolt closing can be indicative of improper case sizing or improper headspace. Hard lift can indicate excessive pressure. These are not absolute, and I am NOT a match gunsmith only a simple armorer. However the rifles that had the problems did not have them when we started shooting in the dry weather. It was only after a good soaking that they began to have issues.
I can speculate that hydraulic pressure was the main culprit. If you are running fire-formed brass in a tight chamber, you still have a little air gap due to the elastic properties of brass. When you sit in a pouring rain, even the most doting shooter will get water in the action. This water takes up space in the chamber. A cold chamber can't cook the water off. When you chamber the round it's like running a piston in a hydraulic cylinder. It's going to take more pressure to force what water you can out. Thus your hard bolt closing.
When you fire that round, the water is still there for a split second before it's burned off. By the time the water is burned off, the bullet is already out of the barrel. Since the water prevented some of the brass' radial stretch I can surmise that the case capacity was slightly decreased. This increases pressure in the chamber and causes the case head to exert more pressure on the bolt face. This results in the same hard bolt lift as an overpressure round.
Now a lot of this is speculation and there may be an engineer our there shaking his head, however it's my best SWAG at what was going on.
Now lets take a quick look at the rifles that did not experience any issues. The one I had the most experience was my own. It's the rifle pictured above. I run an almost stock Remington 700 .308 with a 26" barrel. I won't bore you with the details of the rest of the rifle except to say that the chamber is pretty sloppy and the action is well worn from lots of dry fire. For this competition I was running fire formed, neck sized Winchester brass, but I was running a moderate powder charge. I did nothing special to keep water out of my action and the only concession to the weather that I made was to lower my muzzle so that no water crept into the bore.
Another shooter next to me was running a factory 700P on the first day, but switched to an AW because the bipod stud ripped out of the bottom of his HS Precision stock. Two other LE shooters were running AI AE's and two of our northern neighbors were running custom 700's. All were shooting factory ammo. None experienced any failures. Of course all of these rifles had operated in the weather before.
The reason I enjoy tactical matches so much is that equipment is generally not the great equalizer. It's the shooter's ability to utilize his equipment to the maximum. When I was evaluating what rifle to take to the match I analyzed the courses of fire. I saw that there was a lot of sub-600 yard shooting with positions and time limits. I almost selected my AR10 to shoot the match. It's a custom rifle with a Noveske barrel. It is most certainly capable of the accuracy required. I could have installed my USO on it and shot it well. However since I only had 300 rounds on it, I am nowhere near as proficient with it as I am with my top-feeding 700. I have demonstrated time and time again that I can run the 700 "almost" as fast as the AR10. The speed difference is made up for by the familiarity of the system and the absolute reliability it has demonstrated for me. It is my duty rifle and I know it will function in the mud, grime and rain.
In the end it's the Indian, not the bow. If you are selecting a rifle for a tactical competition, I suggest you go with what you know. A $3000 rifle that you put $2000 worth of ammo down the tube will serve you better than a $5000 custom. If you do choose to go the custom route, then don't blindly chase "accuracy". Instead keep the end-use in mind. Tell your builder you want it to function in the rain, dirt and show. When you roll up your handloads, don't run the ragged edge of pressure. Back it down and hit that accuracy node that leaves room for the heat and rain.
When it's all said and done, get to the range. Because no level of equipment in this game can replace skill with the weapon. Lack of range time has bitten me in the ass before and it will again. No matter what you have done in the past, long range shooing is a perishable skill.
Photo courtesy of Joysoflifephotography.com
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