Some .308 won't chamber

The guy enouraging folks not to neck resize, is shooting rifles with "custom chambers" which are tight, often right on or even smaller than minimum specs and require special dies to size down the cases and necks.

OP, you're shooting an an off the shelf rifle, with likely a reasonably normal, commercial grade chamber, which may just be on the minimum spec side of mean measurement.

Big difference between what the fellow in the video is decrying and the reality of an off the shelf commercial offering.
 
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Well - I'm not a fully invested precision rifle shooter. However, I enjoy getting the most out of my commercial grade rifles, which are capable of outshooting me if "tuned" properly. I did come to the conclusion that traditional FL dies that employ expander balls often cause runout issues. My guess is the expander ball hunts toward the weakest part of the neck. This is very easy to note with a concentricity gage, and you can very easily see the results on the range.
So whats the solution? You can buy fancy and expensive bushing dies that dont employ expander balls, and end up fidding with bushings every time you change brass, or even neck tension, which doesnt suit me. Or you can use an inexpensive collet die and neck size, which also doesnt use expander balls. I go with the latter option. Every few reloading cycles, I have to size the body with either a FL die or a body die, if available.
 
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cosmic said:
Well - I'm not a fully invested precision rifle shooter. However, I enjoy getting the most out of my commercial grade rifles, which are capable of outshooting me if "tuned" properly. I did come to the conclusion that traditional FL dies that employ expander balls often cause runout issues. My guess is the expander ball hunts toward the weakest part of the neck. This is very easy to note with a concentricity gage, and you can very easily see the results on the range.
So whats the solution? You can buy fancy and expensive bushing dies that dont employ expander balls, and end up fidding with bushings every time you change brass, or even neck tension, which doesnt suit me. Or you can use an inexpensive collet die and neck size, which also doesnt use expander balls. I go with the latter option. Every few reloading cycles, I have to size the body with either a FL die or a body die, if available.
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Hornady dies with their mandrel inside neck sizing work quite well and aren't any more expensive than Redding or RCBS.

When a cartridge is sloppy in a chamber, it's not doing anything good for consistent accuracy.

Even a few thousandths of case tilt in the chamber will create consistent accuracy issues. That's why Bench Rest shooters usually have reamers cut to minimu spec and a corresponding set of dies made. Most just use Wilson neck sizing dies with proper neck sizing bushings.

I saw one set up recently where the fellow had a set of dies made up with the same reamer that was used to cut his chamber.

His smith went in with a neck/throating reamer and opened up the neck by .003 inches, to alleviate any chance of the cases not chambering. The rifle was chambered for 308 Palma.
 
I just picked up a couple of Redding body dies. I have rifles with tight head space and have loaded rounds with not enough shoulder bump to chamber. I had thought it was a ridge also due to poor brass prep. Covered the rounds in sharpie and found out it was contacting on the shoulder. The beauty of the Redding body die is you can bump back the shoulders of loaded rounds. I did this and sure enough they chambered. The die doesn’t disturb your case neck. It is also much more pleasant to use compared to a full length die. I don’t like to size the neck, body and shoulder all at the same time, just too much going on to get a feel for what you are doing. It’s easy to over lubricate with a full length die and dent the shoulder. The lubricant with a body die would just flow up the top of the open die.

I guess if your case neck was really burred too much you would know because your bolt wouldn’t even get close to closing. The case neck would not enter the part of the chamber cut for it because it is not tapered. It would be very obvious what is happening.
 
this is caused by over annealing and to much neck tension, as the bullet boat tail enters the case it tends to flare the case mouth, and because it is not supported in the die it continues to flare as the bullet pushes the case neck out. the easiest way to cure this is to go up a bushing or two when sizing, there is no gain in neck tension sizing 5 thou under or 1 thou under a loaded round as the bullet reshapes the neck when seated and everything you thought you gained is lost when the bullet is seated, to much neck tension also adds to variances in base to ogive, and will eventually split the seating stem in your redding dies
 
That’s interesting. Can you explain why there is no gain in neck tension between sizing 1 thou under to 5 thou under? I think most of us believe that there is. Not that I have any experience adjusting neck tension but everything I read says the more shrink the diameter of the case mouth the more the neck tension increases.

Maybe the op could clarify where the bolt stops when the round won’t chamber. If it’s the case mouth being flared it should stop exactly the neck length short of chambering. I would think this would be very obvious and the shoulder dimensions wouldn’t be suspected at all.
 
redneck09 said:
That’s interesting. Can you explain why there is no gain in neck tension between sizing 1 thou under to 5 thou under? I think most of us believe that there is. Not that I have any experience adjusting neck tension but everything I read says the more shrink the diameter of the case mouth the more the neck tension increases.

Maybe the op could clarify where the bolt stops when the round won’t chamber. If it’s the case mouth being flared it should stop exactly the neck length short of chambering. I would think this would be very obvious and the shoulder dimensions wouldn’t be suspected at all.
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you are expanding the neck back up with a bullet, no different then expanding it back up with a mandrel, as it sits, the brass normalizes and any gain in neck tension is simply lost, the softer the brass, the faster it normalizes. seat a bunch of bullets and the next day pull them with a bullet puller, measure the case necks.....what happened??..........oh.......they normalized and you lost all that extra neck tension that caused you grief when seating bullets......
 
I was loading some 6.5 PRC tonight and ran into the same problem, when I took a closer look at the round, I realized I hadn’t chamfered the case. It was in a small batch of 10 cases. I tried a primed only case and it chambered, but bolt was really hard to close. I inside and outside chamfered the cases and problem went away.
It looked same as the one in your picture.
But who knows.
 
So your saying that when folks are doing load development with different size neck bushings they are completely wasting time and components?

It makes sense to me that the neck tension is probably elastic deformation in the case and there is only so much you can deform metal before it becomes plastic deformation (effectively changing the neck ID). This is true of all metals. So what you suggest must be true, there should be a point where you gain absolutely no neck tension.

So it’s a waste of money to buy a bushing die with a bunch of bushings?
 
redneck09 said:
So your saying that when folks are doing load development with different size neck bushings they are completely wasting time and components?

It makes sense to me that the neck tension is probably elastic deformation in the case and there is only so much you can deform metal before it becomes plastic deformation (effectively changing the neck ID). This is true of all metals. So what you suggest must be true, there should be a point where you gain absolutely no neck tension.

So it’s a waste of money to buy a bushing die with a bunch of bushings?
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brass from different lots has different neck wall thickness, and, as brass is sized and shot multiple times the necks get thinner, requiring a smaller bushing to get consistent neck tension again, back before all the choices we are offered today, we'd simply turn the necks to make them uniform and shoot them until they didn't hold a bullet anymore, then either discard them, or turn them down again and start over, this is part of the reason behind .266,.265,.264,.263.262, and .261 6mmPPC chamber reamers.........case dimensions vary with lot number, thankfully big cmpanies like Redding appreciate this and make all the most common bushings available to us, it's not necessarily about adjusting between 1 and 5 thou neck tension, as the rule of thumb has always been 1, or 2 thou neck tension.......just because a tool is available, doesn't mean you have to use it, but for hundreds of years a lot of guys keep prying stuff with a slotted screw driver.......because they can.......
 
maynard said:
Tumbling with stainless steel pins will damage the case mouth and leave a burr. I don’t see anywhere in your process that states when you chamfer the cases.
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No.it will no damage case. I shoot benchrest. I put 6 ppc case and 30 BR case in the wet tumbler - case that worth close to $180 a 100 and require an lots of work including fire forming. I have Never - Ever seen any damage on the case mouth or anywhere on the case.

I even forgot case overnight and the only things they were shining like gold !
This is a myth that goes around on the net…not reality.
 
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OP- Full length your case. Bump .002 - better .004
Dump your neck only die. Get a full body sizing die with bushing.( you already have them)
Pick up a bushing .003 under your loaded round diameter.
Trim your case to 2.015 unless you shoot a competition bench gun.
Chamfer inside and outside. As per your picture there is not enough.

Those rounds will work and you will loose nothing in accuracy.
Stop annealing after each firing. There is nothing to gain. Once every 4-5 firing to avoid neck split is the only reason to do so.

Even on benchrest gun that shoot in the tenth , we do not neck size only.
Many guys get in trouble - like you - trying Benchrest loading techniques - even old one - like neck sizing only - thinking their load will be more accurate. Not so.
 
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Janeau said:
OP- Full length your case. Bump .002 - better .004
Dump your neck only die. Get a full body sizing die with bushing.( you already have them)
Pick up a bushing .003 under your loaded round diameter.
Trim your case to 2.015 unless you shoot a competition bench gun.
Chamfer inside and outside. As per your picture there is not enough.

Those rounds will work and you will loose nothing in accuracy.
Stop annealing after each firing. There is nothing to gain. Once every 4-5 firing to avoid neck split is the only reason to do so.

Even on benchrest gun that shoot in the tenth , we do not neck size only.
Many guys get in trouble - like you - trying Benchrest loading techniques - even old one - like neck sizing only - thinking their load will be more accurate. Not so.
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What he said.

Your case mouth looks a bit beat up, how often do you trim? Are you using a VLD deburring tool, if not, I'd recommend it.

I really don't understand how the neck sizing fad from 60 years ago is still a thing. If it was, Lyman would still be making the tong tool and 310 dies, they were neck size only. I was an active handloader and shooter in the 70s, and I bought a few used guns. Pretty much all of them had galled locking lugs, thanks to the neck sizing fad prevalent at the time. In defence of the fad, the FL dies of that era were made to fairly miserable tolerances, and usually severely oversized the cases. FL and body sizing dies today are made to better specs. The average rifle had a large chamber as well.

You may want to ask some F class shooters how many times they reload their brass. I'm not in the game, but I do recall reading that they buy lots of new brass and don't shoot them too many times.
 
Whatever you are doing, consistency is the key. I like the forster bushing shoulder bump dies but find every few loadings require a full length sizing. I try to minimize sizing just so the rounds chamber. .001 to .0015.

Any new dies I purchase are full length bushing dies. These days mostly whidden because they seem to have stock. Forster is always back ordered.

Are you running an expanding mandrel through after sizing?

A giraurd power trimmer will make quick work of a pile of brass.

How are you ensuring you are not over annealing? I use an amp so it's easy but flame annealing seems tough to get right.
 
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