Originally Posted by CHARLIEDUECE65
I had a 338 edge built with a remingtom 700 long action. I used a Bartlein barrel 30"finished length. Contour was 1.25 for 5" and tapered to .900 at 30". Anyways I got it back from gunsmith and cannot get a reloaded round to chamber properly. I brought a bullet seated to the length suggested with me when I picked it up and it did not work at his shop. The gunsmith stated that I might have to neck turn my rounds. The round was loaded with the 300 gr sierra. I tried when i got home to seat the round deeper and deeper to see if it was too long for the chamber but this made no difference. I can see a ring on the tapering as the round tapers from the casing to the neck. And when I put pressure on an unloaded round to lock the bolt it appears the tapering area is being pushed inwards. I have just used an .338 expander mandrel alone on the 300 ultra case and also used my custom .338/300 ultra resizing die by redding to see if it is me is who having the problem. Is this a finicky round to reload? Thanks.
Call this gunsmith up and ask him what the neck OD is on the reamer. If he can't tell you that, then I'd really be nervous.
Next. Measure your neck OD on your cases with a bullet inserted. If the chamber isn't .001-.002 larger in radius then that is a big problem. A case neck has to have room to swell up to release the bullet. If the neck is too tight in the chamber it'll cause pressure to rise in a big way and this is (1) dangerous (2) a great way to make a good gun shoot like total crap cause your pressure curves look like a Los Angeles aftershock.
If you have a ring on your brass that tends to suggest poor chip evacuation when the barrel was chambered. If the chamber is all ringed up with grooves then your in for trouble when you start shooting it. Get a flashlight (or better yet a scope) and inspect that chamber for surface inclusions. Take a piece of coat hanger and sharpen it to a point and then put a small bend so that it forms and "L". Lightly drag it along the inside of the chamber. if it falls into any kind of inclusion you are going to have big troubles when you start shooting this thing. Remember, a chamber is just like a mold and your case is the casting. If there is a surface inclusion that causes a mechanical lock anywhere you will go through hell getting that case back out.
Assuming the first two items check out now we look to brass and dies.
Necks too long? This is easy to spot. the case mouth will roll in towards the center along the flange.
Appropriate neck bushing being used?
--Do you know how to measure for the right neck bushing? Measure the bullet diameter and add the wall thickness of the neck (X2) and then subtract .0015-.003 depending on the application. That number should be the bushing you use to size your necks.
If it's a single shot I'd go on the light side since they won't be rattling around in a mag box. You just need them tight enough so that the bullets don't seat themselves deeper while driving to the range.
Repeating rifles tend to need a little more so the bullets stay put during recoil. Crimps being the last resort of course.
Also, how are you bumping up the neck size from 300 to 338? A great tool for this is the neck mandrel die that Sinclair International sells. The mandrels are affordable and it'll do almost any caliber. If you order one, ask for Phil Hoham. Awesome guy.
All new cases should be run through a mandrel just to get the necks round and straight again. Those little nicks and dings are hell on bullet jackets. I also make it a point to ditch the expander ball/mandrel in a sizing die. I use an RCBS universal decapping die to get the primers out. This way I'm not running dirty brass straight from the field through a 200 dollar die set. I wash and then polish everything first before I start sizing cases. (boiling cases in simple green inside a commercial deep fryer is a great way to clean brass. Makes the reloading room smell good afterwards too)
Last, before you go attempting to chamber loaded rounds ensure that all your brass cycles through the action first. This is a good QC step for any kind of reloading. Murphy and his dipchit law is always there waiting. . .
What I typically do with this kind of stuff on the initial loading/preparation is intentionally push the shoulder back a little further than I really need to. I then seat the bullet long so that it really bites the lands. This makes sure that the case rim is shoved back flush with the bolt face. Fire form the cases and the pressure will blow the shoulder out to the proper dimension. Back the load of a ways but use a heavy bullet. this will get you a fire formed case that emulates the chamber well.
Yeah, some say that it stretches the web area too much this way but I don't buy it. Most of the cartridge surface area is located behind the shoulder. This is the biggest part of the case. So it has the biggest purchase/contact with the chamber. It's not going to move anywhere if the rim is against the bolt face. The shoulder is the path of least resistance so it just gets blown forward till it catches back up with the chamber. The trick is making sure (knowing) the rim is firmly seated against the bolt face and seating a long heavy bullet well into the lands does this.
I've done this for all my wildcats and Ackley (Ackley did stuff this way too btw-its where I learned it) cartridges and it's never screwed me once.