New Rifle Possible issues??

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Shumba, Jan 4, 2012.

  1. Shumba

    Shumba Well-Known Member

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    My hunting partner recently received a new rifle he had built by a reputable builder. A 300 WM with high end componets, Defiance action, Kreiger bbl, McMillan stock.

    I have the rifle and have done the break in and fired several load development groups. He does not handload so I typically hook him up with this service, he buys the beer in exchange.

    I noticed this weekend while carrying the rifle into my shop after shooting that something sounded "loose" in the action area. I shook it around thinking it was the mag box and realized it was the bolt. I put the rifle in my vise and started playing with it. After releasing the firing Pin the bolt has IMO substantial play horizontally, front to back. To my eye it looks like @ .050 movement. When you dry fire it the bolt visibly jumps forward. I assume this to be excess gap in the lug abutment area. To verify what that gap was I started stacking small cut pieces of duct tape on the front of the lugs and closing the bolt until the play was eliminated. I ended up with 6 pieces stacked on the lugs .036 thickness. It does not appear that the tape is contacting the barrel yet but the "play" feels similar to my rifles now. I put one piece of tape on the front of my defiance 338 Edge ant it bound up when I tried to close the bolt.

    The rifle acts like it wants to shoot with the few groups I have fired being sub MOA. My primitive test tells me there appears to be from .040-.045 gap between th lugs and the barrel (my test could be complete crap too) If this is the case what are the dangers? Will this adversely affect accuracy, what's will it take to fix it? And lastly is this a major eff up on part of the gunsmith or is it something that happens occasionally? I want to know if this is grounds for adding this builder to the BANNED list!.... Lol.
     
  2. shortgrass

    shortgrass Well-Known Member

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    Has the 'smith that built the rifle been contacted about the suspected problems? Disassembly and precise measurement (with a micrometer) is the only way to know what's going on, for sure. Speculation is just that,,,, speculation. Contact the builder, see what he says.
     
  3. Hired Gun

    Hired Gun Well-Known Member

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    Time for a head space check too. How much tape can you get on the base of a new brass before it's tight? How much longer is your fired brass over the new brass at the shoulder? For the bolt to have that much end play there must be a bit of unsupported brass. I would not fire this anymore until this is corrected. To fix this the barrel will need setback.
     
  4. Shumba

    Shumba Well-Known Member

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    I checked the headspace and no issue there but I thought about that and it makes sense to me that there wouldn't nesecarily have to be a headspace problem. Correct me if I'm wrong but the abutment gap is already set before chambering and when the go/ no go gauges ate used the will still give proper headspace as the gap is already there, BUT the unsupported case issue you mention is my concern. As well as this scenario can't be beneficial to accuracy. I am going to see his smith today. I wanted to hear points and opinions from guys here before I talked to him though.
     
  5. 7stw

    7stw Well-Known Member

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    IMHO, it is "acceptable " to have some play on a empty chamber, but NOT when there is a round in the chamber. The .300 win. Mag headspaces on the belt. With a round in the chamber the play you are experiencing should be quite less. I could be wrong on the dimension, but most say that with a round in the chamber, and apiece of scotch tape on the butt end of the brass, it should be a TIGHT closing of the bolt at that point. Again when in doubt, check with your "smith " to be sure. AIM SMALL, MISS SMALL:)gun). 7STW
     
  6. rscott5028

    rscott5028 Well-Known Member

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    According to John Hinant's book, "The Complete Guide to Precision Rifle Barrel Fitting", there should be no more than .005" gap between the barrel breech and the foremost part of the bolt.

    So, it may well headspace correctly. But, sounds like too much gap between the bolt and breech.

    You need to return it to the smith and give him a chance to make it right before blacklisting him.

    -- richard
     
  7. big mike 2121

    big mike 2121 Well-Known Member

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    thats why he didnt drop any names. could have been a mistake on smiths part that he is willing to make good. Making it right will get him more work in the future (i think)
     
  8. Shumba

    Shumba Well-Known Member

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    I went by the smith yesterday and talked with him about the possible issue. He said that there was no problem. The man is a very nice and easy to talk to person that I have done business with for a lot of years and has always done good work, this is why I had my hunting partner have him build this rifle. Plus he is local which is convienient. He said as long as there was not a headspace issue, which there is not, he checked, it will not hurt anything. He said since it is a hunting rifle it needs to have a little space there to keep from locking up if some debris gets into the action. I see the merits of this but if it is my rifle and I paid $1k plus for a custom BR quality action, I want it built to BR tolerances that will lock up if frog hair gets int the lug recess. I will worry about keeping the action free of debris. My hunting partner probably could care less and ultimately he is the owner of the rifle, as long as it is safe and he can hit a deer out to 300 yards all is well.

    I still do not know what the actual "gap" is in the abutment area on this rifle except what I derived from my rudimentary test. However; I would like to know that if there is this excess gap then what is the possible effects on accuracy. The builder says it will not effect anything accuracy wise and there is not a safety concern. I guess I will leave it at that and if it does not end up being a shooter or if brass problems start showing up during load development i will know that there is indeed an issue here. It just does not seem right for a high end rifle built from these componets to sound loose and rattle around like a fishing lure full of BB's. If it was my rifle it would drive me crazy....but thats me...I guess if it was a shooter and didnt blow me up I could get over it.......:D

    Thanks for all the replies, if anyone has any other insight it is welcomed.
     
  9. rscott5028

    rscott5028 Well-Known Member

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    Shumba,

    If you're in Fort Worth, take it over to S&S Precision in Argyle and ask them to have a look. It's worth the trip even if you don't want to discuss the rifle.

    You might even take a couple of pieces of fired brass from your load workup. Preferably some that were just starting to show pressure.

    Otherwise, we're just speculating like Shortgrass stated at the beginning of the thread.

    -- Richard
     
  10. Shumba

    Shumba Well-Known Member

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    Thanks to the help of some great members here I was able to accurately measure the distance between the bolt nose and the recess around the chamber. The measurement is .040. Should I be concerned with this tolerance.