Bumping shoulder on case

[Jonl]

Been reloading forever but just getting into long range and or precision. How exactly do you bump the shoulder back . I am reloading 22-250 with a redding neck sizing die.When the die touches the shell holder it doesn' t appear to touch the case except the neck. Where and how do you measure bumping the shoulder. I also have not gotten clear in my head why this rifle with the factory barrel would handle 52 gr bullets and h380 up to 38 grains with no pressure signs but not exceptional accuracy. Put on a McGowen barrel and accuracy was spectacular but bolt started sticking at33 gr. and showed other pressure signs. Using virgin Win brass full length sized and Cci Br primers and Rem magnum primers and once fired neck sized it doesn't, change. checked case length, turned necks, seated deeper still can't go past 32.5 gr. Set Headspace with a Forster go gage . Can't see how tight chamber could do this as some suggested. Just got chrono and can't wait to see what velocity is. can a match barrel get higher velocity with less powder? I did not find a no go gage to check but I was surprised when I called Forster to see the difference between go a.nd no go length and he said .005". If I remember correctly threads on savage are 20 tpi so if my math is right the difference would be 1/10th revolution of the barrel.

 

[K22]

You can't bump the shoulder back with a neck sizing die, you need a full length sizing die.

For bolt rifles, the optimum bump is .001 to .002. To measure the bump accurately, you need a tool such as the Hornady Lock N Load Head space Gauge. See Midway or Sinclair catalogs.

Read the article on the riflemansjournal.blogspot.com entitled "Basics - Resizing - Case Dimensions". This explains the process and equipment to produce the desired shoulder bump (set back).

In my opinion and experience, the shoulder bump method of sizing produces the most uniform and best functional reloads. If done properly, it does not reduce case life anymore than neck sizing.

 

[Smalltruck]

I went through this on my 20 practical, some would stick and others wouldn't. So some close inspection was called for. It may be that your shoulder needs to be bumped on mine it was the neck diameter.

Heres what and where I found it, my redding neck die with a 226 bushing would resize the neck for about .144 and leave a slight donut that didn't get sized at the shoulder neck junction. My signs were bolt was stiff to close, or wouldn't close at all, bolt was stiff to open when I know too much powder wasn't the problem, blown or cratered primers.

The blown primers were a simple fix, change to BR4's and that problem went away. But that donut was really not excess brass, it was a section of the neck that didn't get resized. I wound up spending about an hour at the local gun store measuring dies sets with my caliper until I found one where the dimensions were right. (note this does not mean that other dies were wrong, I had a very specific need)

When I ran my brass through the new full length die and got the whole neck sized my stiff bolt problem went away

 

[22BRGUY]

I shot and reloaded for 22 250 for almost 30 years and learned a lot. Although in it's day, the 22 250 cartridge was superb and still is very respectable, it's cartridge design has some to be desired. The body taper and the shallow shoulder angle tend to lend themselves to case growth and therefore donuts. The best way to deal with this problem IMHO is to turn the necks with something like the 21st Century neck turner and turn up into the shoulder so when the case does grow, it won't form donuts. Secondly, as mentioned , you will need a tool to measure the datum length (case head to middle of shoulder) like the Hornady Lock N Load tool mentioned. On new brass, I like to measure the datum length before firing, then fireform the cases, and then fire once more with neck sizing only to make sure the cases are fireformed to your chamber. Once the cases have been fired twice, measure the datum length and then bump the shoulders only either using a Redding body die or a Redding FL type S die without a bushing to just bump back the shoulders ,001 to .002 shorter than the twice fired length. A good way to find out what is the right amount of shoulder bump is to remove the firing pin from your bolt and after bumping the shoulders, chamber the case and the bolt should go down without resistance except for the last 1/4 of the bolt close where there should be mild resistance. Then from there you can size the neck with more or less neck tension depending on if you want to target shoot or take it in the field. Best Wishes and hope this helps in some way.

 

[Jonl]

I used Redding dies that came with a rifle that I bought a while back to reload for this rifle. I couldn't understand why the cases would stick on relatively mild loads and factory ammo shot fine. It was a three piece die set and I had it in my mind that the Redding dies might be better than an old RCBS set that I've had for a long time. Even full length resized cases would require a liittle effort to close the bolt and the bolt was hard to open and extract the cases.. I dug out the RCBS die and full length sized some cases and my sticky case problem has disappeared. What is that about? I thought I would probably get better accuracy neck sizing fire formed cases after fl sizing them initially but I could not without the cases sticking.

 

[Smalltruck]

Try this trick, when you adjust the die in your press, screw it in one turn past contact and run a case that way. Some presses run out of travel when they are close to the end of stroke.

 

['Freak]

One full turn on a 7/8-14 thread will move that die .071” which gonna be too much. Only an 8th of a turn in beyond just touching top of the shell holder is .0089” and that may still end up being too much. Main thing is when you turn the die in beyond just touching it will size further down on the case and bump the shoulder, but you don’t want to go too far in the other direction either.

I prefer using a shell holder made by the same folk that make the die, swapping shell holders can make a difference. You need to use a device that will allow you to measure distance of case head to shoulder. Using that dimension from a case fired formed to your chamber, adjust the die to bump the shoulder back so its dimension ends up a couple or three thousandths less than that of the fire formed case.

Also, when you’re neck only sizing you don’t have to size the entire length of the neck. Smut up the neck then adjust your neck die so it will rub away however far down the neck you want to go, like half way or 2/3 or maybe a bullet diameter.

 

[amamnn]

For at least the last three years it is no longer true that you cannot reset the shoulder length using a neck die. Forster makes a neck/bushing /bump die that you can use to reset both the neck and shoulder--or just the neck--or just the shoulder--a great tool. I have used this die in the 6mmBR Norma and 22 BR cartridges, the .223 Rem and .243 WSSM. It works as advertised as do all the Forster products I have used so far. This die does the same job as the Redding body bump die, which I also own, having bought one before the Forster die was on the market. However, the Forster neck/bushing/bump die is more versatile and possibly less expensive, I do not really remember what I paid for the various dies--the goal being accuracy not frugality......

 

[22BRGUY]

One other thought would be to size 2 cases, one in each die, and then measure the diameter of the case just ahead of the extractor groove in the case heads. If the RCBS diameter is smaller, then you may want to try a small base body die as that might be where the sticking is coming into play. If you look closely at the cases, you may notice scuff marks to tell you where the problem is.