I recieved my custom 300WM last week and finally felt well enough to inspect the chamber and becamed a concerned about the amount of freebore. An email was sent to the smith but thought I post my concerns here for qualified opinions.
Chambered for 300WM Lapua reamer. I sent three dummy rounds which cleared the magazine easily. I elected to throat the chamber for 180 grain Barnes TTSX. The dummy rounds measure to ogive were 2.734. Today I used my stoney point OAL gauge and determine Loaded round with ogive touching lands is 3.004. The smith and I were aware of Barnes recommended jump of .050. To load for this chamber my round will be loaded 2.954, which is way off from the dummy round provided of 2.734. This is a difference of .22.
I can seat my TTSX out to 2.954 (ogive) for the .050 jump but this makes the tip fairly close to my magazine. I doubt I will have any room to chase the lands and concerned proper feeding at critical moment. All measurements are to ogive with use of comparator.
I'm looking for options available to me. I know this will be discussed with the smith but any additional hints or recommendations would be appreciative. The smith used is a very well known and respected so I have no worries with any follow up support.
Well thats alot more freebore than what you wanted and your right about not being able to seat the bullets out to chase the lands as it wears. Did the smith use a throat-less reamer then ream the throat by hand to match your rounds? It appears not.
It seams to me that the barrel should be setback about 1/4" and rechambered correctly to match your wanted dummy rounds.
I had heard about Pac-Nor doing this same things for a fella that wanted a 300 Wby with no freebore so he sen't them dummy rounds and he got back a gun that had more frebore than a factroy Wby.!! , they replaced the barrel because it came up 1/2" shorter than he ordered and he threw a fit about rather than letting them set it back.
Anyhow if the smith is a good guy it should be no trouble for him to make this right to make the customer happy. It only makes sense for him to do this because in this game one mad customer can ruin your buisness , for example one of the great guys here that everybody knows and respects build you a gun and its not what you want , won't shoot or whatever and doesen't make it right , well then you come here talking abut how this guy did you wrong ,that alone can cost that smith a ton of money just by putting a little bit of doubt in the minds of potential customers.
I figured out the problem, my measurement was flawed. Turns out the Stoney Point modified case wasn't fitting into the .337 neck completely. This exaggerated the measurement considerably. After I turned the neck of the modified I was on the money.
Reminds me of the days I did construction, measure twice cut once.
I appreciate the help. It's a relief knowing the chamber was cut as requested.
I own a (olympic) Hammerli tanner 300 meter match rifle in 308 win. and the freebore on this thing was enormous, even with the 200SMK I could not touch the lands...while trying to measure my maxoal lenght.
the rifle is a .200 MOA even with peepsights, it gave me a group of 1 7/8 inches at 500 meters...for three shots.
I would not be too scared of your freebore. the groups will have the last words.
Jose Marine you make a valid point. Fortunately the problem is nonexistent. I was worried that If I had to seat the TSX way out, I would really be out of luck with the shorter non-monolithic bullets such as Accubonds, Bergers and such. Although I had the chamber targeted for the TSX, I'm glad I have a little wiggle room for other bullets.