6.5 WSM rebarrel problems
Guys I would really appreciate some help with this because it?s been a real head scratcher for me.
I had a win model 70 stainless featherweight 300 WSM rebarreled to 6.5 WSM.
Kept it 24? and the same barrel contour. I?ve been necking 270 WSM brass down and I do have to neck turn as the reamer my smith used is kinda tight (brass necks measure .2978 after firing).
I started the process of working up some loads for it and after a few outings decided that my gunsmith did not throat it out to the length I wanted. I took it back and he graciously agreed to throat it out further but he wanted me to make some ?dummy? rounds the length I wanted. I gave him the rounds and he throated it out. When I picked it up the dummy rounds chambered with no resistance and I was able to set my bullets (140 Berger elite hunters) out to just under my magazine length. Perfect.
I have shot it approx 50 times since then and now the dummy rounds will no longer chamber and I had to decrease my OAL by 0.035 to get it to chamber with no resistance
The barrel is clean. The throat area is clean and I have looked at everything I know to do. I thought it had to be something I was doing or maybe I had somehow made a mistake. However my dummy rounds that I provided the gunsmith no longer fit and they haven?t changed.
The witness marks left on the bullets that meet resistance don?t show the lands. They have an even Mark all the way around like the lead in is to tight.
What in the world could cause this. 50 rounds and now I have to back OAL back .035?
Any help would be appreciated. I would hate to carry this back to the same smith that has already did work on this a second time already and it something that is my bad.
Oh also accuracy was excellent the first 20 or so shots after getting it throated out and then fell off but not that bad (from sub moa to 1.5?) however I changed to a different powder about mid way through the session so it may be nothing.
Thanks for you responses so far.
To answer a few questions
I am not aware of any factory loads that I could try. This is a wildcat.
Also I am full length sizing and I checked the casings for run out and that doesn?t seem to be an issue.
I however have not used a borescope to check my chamber and throat I just did a visual with a light. I will do this soon as I get access to a borescope. I have also not checked the bolt lug recesses.
Thank for the help so far. I will post what I find and please chime in with any other ideas. I will try to post a photo of the bullet in the dummy round that I forced partially into my chamber.
I had a win model 70 stainless featherweight 300 WSM rebarreled to 6.5 WSM.
Kept it 24? and the same barrel contour. I?ve been necking 270 WSM brass down and I do have to neck turn as the reamer my smith used is kinda tight (brass necks measure .2978 after firing).
I started the process of working up some loads for it and after a few outings decided that my gunsmith did not throat it out to the length I wanted. I took it back and he graciously agreed to throat it out further but he wanted me to make some ?dummy? rounds the length I wanted. I gave him the rounds and he throated it out. When I picked it up the dummy rounds chambered with no resistance and I was able to set my bullets (140 Berger elite hunters) out to just under my magazine length. Perfect.
I have shot it approx 50 times since then and now the dummy rounds will no longer chamber and I had to decrease my OAL by 0.035 to get it to chamber with no resistance
The barrel is clean. The throat area is clean and I have looked at everything I know to do. I thought it had to be something I was doing or maybe I had somehow made a mistake. However my dummy rounds that I provided the gunsmith no longer fit and they haven?t changed.
The witness marks left on the bullets that meet resistance don?t show the lands. They have an even Mark all the way around like the lead in is to tight.
What in the world could cause this. 50 rounds and now I have to back OAL back .035?
Any help would be appreciated. I would hate to carry this back to the same smith that has already did work on this a second time already and it something that is my bad.
Oh also accuracy was excellent the first 20 or so shots after getting it throated out and then fell off but not that bad (from sub moa to 1.5?) however I changed to a different powder about mid way through the session so it may be nothing.
Thanks for you responses so far.
To answer a few questions
I am not aware of any factory loads that I could try. This is a wildcat.
Also I am full length sizing and I checked the casings for run out and that doesn?t seem to be an issue.
I however have not used a borescope to check my chamber and throat I just did a visual with a light. I will do this soon as I get access to a borescope. I have also not checked the bolt lug recesses.
Thank for the help so far. I will post what I find and please chime in with any other ideas. I will try to post a photo of the bullet in the dummy round that I forced partially into my chamber.
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Check all your fired brass, for OAL. The neck turning, might have caused one of your reloads. To break off, a small piece of of brass in the lead. 0 -
Have you cleaned the bolt lug recesses? Residue from "throating", brass shavings, and whatever may have built up there. 0 -
Try some factory loads and see if things improve. 0 -
Very interesting. +1 for a really good cleaning of the bore and chamber with a good copper solvent and clean & check the bolt, especially the extractor zone. Clean the bolt recess in the receiver too. Careful inspection of your cases is always a good idea. Are you neck sizing only? Cases are round when checked with a micrometer in the locked position. Set the case on a flat surface, rotate it while looking directly across the case mouth. Or put it in the case trimmer an every so lightly touch it with the cutter - full even cut (sharpie black works good here) is what you want to see.
When fire forming, I use a cast bullet with a mild load. The bullet is seated out to engage the rifling - this helps hold the undersized case in alignment. I like chambers that I can drop the spent brass back in and spin the case using a pick - that's a round chamber in my book.
Bullet alignment in the case can be an issue with handling, those low drag designs don't have a lot of bearing area to help hold them straight. Generally I set my bullets out about .003 to .005 as calculated by the seating stem thread pitch. I uses a candle or stick match soot on the bullet - sharpie black is too thin.
Changing powder, even lots of the same stuff will/could change everything.0 -
I would take it back to the smithy along with the dummy rounds and see if he has an answer, it could be an issue with the barrel itself. 0 -
By coincidence had the same thing happen to me yesterday. FN 57 pistol, with some of my handloads. Out in the desert, all of a sudden. Wouldn't chamber either my ammo, or Federal factory.
Took it apart this morning. Had a complete separation, just forward of the shoulder.Got it out with a over sized bore brush, forced into the chamber. Used a brass cleaning rod, from the muzzle to drift it out. Looks like I have to be really careful, reloading for the 5.7. Supposedly it was once fired brass. I got from Amazon of all places. Silly me.0 -
From the Breger website...
""The Elite Hunter line of Hybrid Hunting Bullet was designed for shooters that are using custom rifles and are not limited to SAAMI dimensional standards and bullet seating depths. These bullets have a longer nose than the classic hunter bullet line providing hunters with the best ballistic performance possible""
Me thinks you have buildup in the lead-in area of the throat. A different lead may be needed for loads.0 -
Deltaoutdoorsman,
Babun is on the right track, I think.
Normally, when we prep brass for reloading, we shorten the case by 10 or 15 thousandths (0.010" - 0.015") in order to prevent the case mouth from getting crushed into the neck area of the chamber. This puts pressure on the bullet and raises pressure in a bad way. The unfortunate point is that this area in front of the neck in the chamber will gather fouling and some of it can be the hard stuff like carbon fouling. It's easy to see with a good borescope, just go slow and watch for the neck junction in the chamber.
Best.0
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