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Everyone has a different idea about what makes a better handguard mount system. Some require special hangers, some are freefloated, some have metal cups to contain the head of the screw, and yet others are just the way they came from the TC factory. The 50/50 benchrest folks make a big deal of micro-tightening hold down screws and using mini torque wrenches to be consistent. What works best for you and how do you tighten your handguard screws? How do rest your handguard/barrel when bench testing (specially thoser of you that shot in that last competition)? LouisB Nosey folks want to know! | ||
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TCL, Here you posted this question a couple of days ago and the gang hasn't jumped on it - I'm surprised. Well, I have a few thoughts about your question, and I don't push my thought as the last word, but this can serve as a motivation to think about a subject that I do think is important. and your bringing it up is a good move. I didn't shoot in the "postal matches", but have given this issue quite a bit of thought and have tried several different things. Some work and some don't. First, I think consistency is the real key. Just doing things the same way every time - even if you screw up, do it the same way every time. Next, there are some forepiece modifications one can make, especially with the Contender that do help. I use the hanger bar on all my Contender barrels. But I make some modifications that I think are worthwhile. One is that I make the hangar bar out of ordinary 5/16" key stock. It is no big deal, although it does take some careful drilling, threading and filing. After the hangar bar has been fit to the barrel, I "egg out" the front hole with a small round file so there is about .006" or .007" lengthwise play (but no sidewise play) in the front hole. Next, I file a hold-down screw so it will bottom on the barrel under the dovetail and so the front of the hanger bar can just barely slip a few thousandths lengthwise, but not sideways or up and down. Then "Lock Tight the threads in place where it is just slightly (slip-fit) loose. Next, tie down the back screw solid and lock tight it in place. Why? Well, as you shoot, the barrel will warm up or heat up and expand, but the hanger bar will not. If the hanger bar is tied down solid at both ends, there is the potential for vertical stringing depending on how hot you get your barrel. And yes, I have seen the vertical stringing without this sort of exercise. Next, I make my forepieces, and those I use for testing are made with a 2 1/2" wide, completely flat bottom, sideways and fore-aft. I also shoot test loads from an adjustable, stepped shooting platform. This also involves installation of a wedge under the butt piece so the Contender sits flat, can be moved just a little, but the shooting position is almost always the same. This system I use is a lot like the one Don Bower uses, and it is noteworthy that we each came up with the same kind of shooting platform about the same time, but independently. With these modifications, then being attentitive to shooting with the same grip as much as possible, the chances of reducing the size of the group is higher. There are other things too that will help reduce the size of the group, like work with the brass, load development, Tweeking with your adjustable objective on the scope, etc, but they do involve considerable effort. Each of these thing individually doesn't make much difference, but collectively, they can make an ordinary barrel shoot pretty impressive groups. And, if you are one of those guys (like me) who is trying to sqweeze that last little bit out of your Contender, it is worthwhile. I can show some pretty good results from this sort of effort too. With my 14" Bullberry 223 Match barrel, I have shot repeated 0.250 5-shot groups. With the 14" 7 mm Bellm, 0.500 groups, with the 308 Bellm, 0.300 groups. With the .358 Bellm, 0.400 groups. With my original 14", 14 twist 30-30 barrel, .375 groups. With the 20" 25-35 Imgram Improved carbine barrel, .375" groups. With the 18" 22 K-Hornet, .500 groups. I do have to admit that my efforts don't always work wonders though. I have evaluated a few barrels that no matter what I did they simply wouldn't shoot under 1.5" (one, being the most beautiful .309 I've ever seen wouldn't shoot under 2"). Why? I've never figured out why. Lets kick this one around a bit. Don Shearer | |||
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quote:Don, Excellent post! I have found the above to be the case in my shooting as well. Though I do not employ a rest such as yours or Bower's, I do use the same sort of forends from Bullberry and VVCG, and employ an elevation wedge under the grip. My front rest in the field is a Harris BR 6-9" bipod, and for testing, both the bipod and a mechanical forend rest with a leather sandbag. One question for you: does your hangerbar use one or two screws to hold the forend to the bar? I find that when using the two-screw hanger bar system [that VVCG now offers which uses two screws to hold the forend to the bar, and in turn two more screws to hold the bar to the barrel], my shooting is more accurate than when I use their standard one screw hanger bar setup, where there are two screws holding the bar to the barrel [and in both the holes are slotted such as you describe in your system] yet only one screw holding the forend to the hanger bar. As well, their aluminum pillar bedding system seems a very good alternative to the hanger bar method, as the forend they provided for my testing of the joint Bellm VVCG .223rem barrel performed well, though again, their two screw hangerbar system outperformed the pillar bedded forend a bit, though by comparison the two screw forend I had them make to my specs, significantly outweighs the other VVCG and Bullberry forends that I use, so the analogy is not "one to one" in all other respects. I know what you mean by barrels that simply will not shoot no matter the care placed into loading, resting, etc. Over the lastseveral months, I shot such a barrel for a friend of mine that despite my best efforts, would simply NOT perform, though we believe the problem has been identified as a slightly too short of a throat Makes these tests "brain teasers" to a degree | |||
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Louis, I haven’t seen you at the Owl Hollow range since early spring, but from reading your posts, you seem to have been busy. If you remember, I was shooting a 222Rem at the range the day that we met. Well, it took me quite a while and several hundred bullets, but I finally got the barrel to shoot under � MOA. It was good enough to take second place in the recent postal match. I used several types of rests, plus several types of forends before I managed to get the barrel to shoot consistently. I tried the Caldwell pistol rest, which was steady as a rock, but couldn’t get the results that I wanted. I finally settled on using one sandbag under the forend, with the pistol pushed forward until the trigger guard was touching the bag. I didn’t use any rear support, and usually shot one handed with a very light grip. Basically, I just let the gun sit on the bag with as little interference as possible. The forend that I used is one that I made myself. I don’t use a hanger bar, but the forend only touches the barrel at the two dovetail mounts. I also use thin rubber washers between the wood and the mounts and just tighten the screws until they are snug. The forend will move with slight pressure, but seems to return to the same position after each shot. I added 8.5 oz of lead to the forend when I tried a 24X rifle scope on the pistol to help hold it down on the bag. Here is a picture of the 24X scope and home made forend with the Caldwell rest. The second picture is the forend, showing the lead inserts that I added. The same forend seems to help my 35Rem barrel also, but seems to open up the groups on my 7-30Waters. I haven’t figured this one out, but I’ll probably play with changing the weight of the forend to see if it makes any difference. Nashcat | |||
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A couple of good post there by guys who are thinking about the physical processes involved in the performance of their guns. Sean, On my 14" Contenders, I use 2 screws in the hanger bar for bar-to-barrel. The back one is via a tight fitting round hole and the forward one is via an "egged-out" slip-fit hole. The forepiece is held to the hanger bar with just one screw, but I did rout out the channel for the hanger bar to be just a little oversize, then glass-bedded a 1/2" long section at the back and front of the bar. This makes it so the bar bottoms and is aligned on bedding compound, and comes to the same place each time it is attached. On my carbines, I use essentially the same set-up except I make the hanger bar about 8" long and use two screws to hold the forepiece in place - also to bedded sections. I also put the forward one far enough forward so a Snipe Pod and shoulder strap ca be attached. Nascat, I like your idea to rubber-bed the forepiece in place. This will certainly hold it in place, but wont put any pressure as the barrel heats up. Putting balast in the forepiece can help out quite a bit when one is firing a relatively large number of test loads with a chambering that gives lots of recoil. There is a hazard in doing that though in that it is quite possible to literally pull the dovetails out of the barrel. At one point, Mike Bellm was offering to cut oversize dovetails and sell oversize fittings for those who stripped them out. That might be worth filing in a "remember" place for future reference. When I was doing the evaluation and load development of the 358 Bellm (without any muzzle brake) I too used some balast to help out with the recoil. I hollowed out a section in the forepiece and filled it with 7 oz. of lead shot. That helped to control the recoil, but was really to heavy for a field gun. I still shoot the 358 without a muzzle brake, but since I don't have any problem with recoil fatigue until shooting about a dozen shots, I just figure I will have to get my elk with less than a dozen shots. All that is for forepieces used in testing at the range. For a field forepiece, I have made up one that is 2 1/2" wide, with flat bottom and with finger grooves so it matches the old style finger groove butt grip. This also helps get a consistent hold each time I come up to shoot. To the front end of the forepiece, I have attached an extension made of 1/16" X 1" steel strap which extends about 3" forward of the front end of the forepiece. This extenson is for a Snipe Pod and shoulder strap. It gives a long base and helps get a steady hold in a field position. Don Shearer | |||
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