Shoulder bump problem

[msilbernagel]

If you do, I would suggest a very good cleaning of your cases afterwards or your powder will likely catch in the neck when charging the case. It's not a pleasant experience. I have been there and done that.

Makes sense. Would dry (graphite, etc) work better, or should it be necessary at all?

 

[Rset]

Makes sense. Would dry (graphite, etc) work better, or should it be necessary at all?

I have removed the expander balls from all of my dies. If you don't use them, they can't be the problem.

 

[PD Gohil]

I completely agree I overlubed these cases. And I never thought about lubing the inside to assist the expander ball. I will add that to my regimen. Appreciate all the advice guys!

PGohil
WV

 

[K22]

I completely agree I overlubed these cases. And I never thought about lubing the inside to assist the expander ball. I will add that to my regimen. Appreciate all the advice guys!

PGohil
WV

You're probably overwhelmed with responses but I'll add my input to share my thoughts and experiences in a sincere effort to help you. Let me say however, I'm not expert but I've been reloading for about 50 years now and I'm a precision varmint and predator hunter which is not a world class shooting credential .

1. I brush the inside of the necks out with a nylon brush using a low rpm drill. It does a good job of removing carbon deposits on the inside of the neck. With the drill, it only takes a few minutes and reduces drag of the neck when using an expander button

2. If you are seeing carbon deposits on the expander button it's probably a sign that the button is too large or has a rough surface. If you polish the button with 220 grit or finer paper it will put a glass like finish on the button and make it easier to slide through the neck. Just check frequently with a micrometer so you are not removing too much.

There nothing wrong, in my opinion, with using an expander ball as long as it is sized appropriately so it does not distort of length the case. I've been using them for over 50 years. I have about 4 in .001" diameter increments for each caliber that I polished and use the one for a lot of cases / rifle that gives me the desired neck tension.

3. I strongly support full sizing with a shoulder bump especially for hunting reloads but it can be confusing. I've experienced some variation in fired unsized cases headspace the degree of which depends on the quality of the cases and the indiviual rifle. I've seen as much as .002" variation.

4. I use a Whidden bump gauge because it's one piece and eliminates interfaces. If you are using a gauge with inserts, add match marks to the insert and gauge body so you can align them the same each time. This will promote consistency. Also make sure the gauge is align parallel with the jaws of the caliber.

5. Measuing bump is subject to operator error. It takes some practice to obtain uniform results in my experience. The pressure you exert on the caliber and positioning the case will affect consistent measurement. I slightly rotate the case to align it while apply a uniform pressure to the caliper. It helps.

6. Using standard cases, such as Rem / Win / Federal I often get some slight variation in bump, i.e. .001 to .0015. I only check a few, 3 to 4 in the group I'm loading with the bump gauge, usually about 20 to 40 cases.

As long as I'm not extruding the case, the cases chamber flawlessly. I also use a Wilson Case Gauge as a quick qualitative check of all cases after sizing. If the size case is between the upper and lower steps of the gauge then the case is ok and will chamber easily. This works for all chambers that meet SAMMI specs.

7. As cases age harden and if you are not annealing, some die adjustment may become necessary to obtain the desire bump. I don't anneal so my FL die is set up using Skip Shims so I can easily adjust the amount of bump. No matter which shim I'm using, I make sure the shell holder has some degree of cam over to make sure I'm at least contacting the shoulder and not extruding the case during sizing.

8. When you full size, you are also sizing the radial dimension of the case which aids in chambering. I can often full size to a zero bump and the cases chamber flawlessly. The goal is to size only as much as needed so the case chambers with only very slight resistance. So you may ask then why not use a neck sizing die. The answer is because it does not size the radial dimension of the case and in time, which is unpredicable, the case will have difficulty chambering both due to radial and longitudual expansion.

Remember - The only reasons you are sizing to begin with is so the case will chamber properly without oversizing and the case neck will hold a bullet with the desired neck tension