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TC Dimension 308 problem?
olehoss1954
Member Posts: 7 ✭✭
TC Dimension 308, Nightforce NXS 2.5X10-32 scope in QRW rings on the factory provided mounts. Anything over about 5 rounds and the POI shifts up and right. I can usually get about 1" groups out of the first 3 or 4 rounds, which is all TC claims, but when it starts stringing the shots more resemble a pattern than a group. I checked the torque on everything that turns or screws and all is correct. Think a new barrel would help?
Comments
Not a lot of barrels/rifle will continue to shoot sub MOA as they heat up.
Expectations beyond 3 or 4 shots from a light barreled sporter aren't always met.
Bear in mind that Smith & Wesson now owns Thompson Center and there is no mega corporation which is concerned about shooting small groups. Their concern is for profits.
quote: Smith & Wesson is a public company, so what the gun nerds think doesn't always count when you boil everything down to nuts and bolts shareholder profits.
This is a hunting rifle first and foremost. It's not expensive by comparison and they do not bill it as a target shooting rifle for competition. They claim MOA performance and that's what you got. It is a clever answer to all those frugal shooters who think that a switch barrel is the ultimate solution to their needs. The barrels are made to a price point and not for best quality so they are undoubtedly inexpensive button rifled barrels.
Based on the design, a new barrel will either have to come from T/C with no guarantee that it will shoot any better or get a custom made from a talented gunsmith at a potentially much higher price.
No matter what age old techniques you might consider, your best bet is a top quality cut rifled barrel. If you can't get a gunsmith to fit one to this action then I suggest getting rid of this rifle and buy a rifle that is either accurate from the beginning or can be accurized. Or learn to live with hunting accuracy and 3-shot groups. You can still harvest game just like everyone else, you just can't shoot long strings from the bench.
Best.
olehoss1954,
Bear in mind that Smith & Wesson now owns Thompson Center and there is no mega corporation which is concerned about shooting small groups. Their concern is for profits.
This is an example of a true 'cold bore' group since the temps were hovering near zero on the day of the testing. The rifle was custom built used strictly for long range hunting.
This image was made right after the three shot group was executed. It was witnesses by 5 men, three of who used the Vectronix Vector 21 range finders to achieve the correct distance.
The range finders usually sell for $20,000/each on the civilian market so the value or significance in not in question.
I really appreciate your choice of a Nightforce scope for your hunting rifle since it demonstrates your commitment to quality. However, with regard to the rifle, I think you could do better with a different choice in the long run.
Sure you could spend the time and money bedding this rifle and still achieve nearly the same groups. I personally would step up a notch to a better rifle or at least a rifle which could be improved without a ton on money being thrown at it. Bedding the rifle is never a waste so long as the person doing it knows the proper methods and does it on a routine basis. Bedding a couple of rifles a year does not provide the best basis for claiming experience. Be sure to ask for pillar bedding.
The best barrels to use for consistency are cut rifled barrels not button rifles barrels. Bartlein is currently the best of the cut rifle barrel makers. Krieger can be right up there but they are usually second. Then there are the rest of the second tier makers who make good barrels but just haven't hit the top spot yet.
Decide what it is that you want to accomplish then research the products to get you there. If you run into more questions, come back and ask.
Best.
I final test a hunting rifle's true one shot accuracy by firing only one shot at a target over several days with the gun and its ammo subjected to varying temps cold to hot. After several days do a average of the groups as if the ONE shot were all fired at the same target. This test will show if the temperature is causing a shift in the point of impact as the gun and ammo are subjected to varying temperatures.
This one shot point of impact test over several days and varying temperatures also tests the shooter to prove that the rifle is accurate. Will also test the rifle tuner and the reloaders patience if it's not printing accurately. Seen some real head scratchers doing this type test, but I think of it as a hobby and learning experience.
I have tried to add value to your discussion about your rifle but it seems to fall on deaf ears.
In essence, all this discussion about cold bore shots and how to resolve this issue is a non-issue. Mostly mumbo jumbo. Please watch this video made by one of the better shooters in the U.S. which is dedicated to this fallacy:
If you have any other questions please feel free to use my e-mail contact which is located in my profile here at GB.
Best.