Difficult Bullet Seating Experience

[Full Curl]

I was seating some 140gr Nosler Accubond bullets in fired and prep'd 270wsm Nosler cases last night with a Forster microseating die on a co-ax press. Most of the bullets seated just fine, but a few needed a lot more noticeable pressure on the ram to seat them. After further inspection of these, The seating die stem actually marred the bullet very slightly because it was having such a hard time seating which made it a tad bit narrower so it didn't seat as deep as the others by a few .01". I've never had this happen before, so I removed these bullets and used a tiny bit of case lube inside the neck and then seated a new bullet and they all went in to the correct depth very easily. However, they went in almost too easily since the necks were already expanded a little bit from the first bullet I seated and I didn't resize them afterwards, prior to seating the second bullet.

Questions:
(1) Is this a common issue?
(2) Is using a tiny bit of case lube in the necks prior to seating a good idea or not? Any accuracy issues?
(3) Is pulling a bullet and seating another one without resizing the neck going to give me neck tension issues and poor accuracy issues?

Thanks.

 

[243winxb]

1 Not common. How are you sizing the necks/case? An expander, if used should make neck tension all the same. If using a bushing die, with unturned brass, seating pressure will be different. No ring should be left on the ogive of a bullet.


2 I use a nylon brush to clean and lube inside the case neck. RCBS lube. There are other dry lubes, i have not tried.

3 The neck tension can differ due to brass hardness, annealing. Its best to resize the neck/brass after pulling a bullet. To many variables.

 

[Full Curl]

Thanks. I'm bumping shoulders back with a FL Foster die that has an expander ball. I have never lubed or needed to lube inside the case neck before seating bullets. I too use a nylon brush to clean before loading but have never added lube this way. I also use RCBS lube. Now I'm thinking I should have marked the cases that I pulled bullets on... not sure which ones I did that with. Good thing I only loaded up 25 rounds I guess. Glad to know that others at least lube inside case necks. Thanks.

 

[g0rd0]

sounds like you have a problem. Are all of your necks the same thickness? If so have you annealed lately?
I think that the wall thickness of your necks may not be consistant. I would first anneal then if you are having the same issues you may need to turn the necks

 

[Mikecr]

I'm thinking you're way oversizing necks.
When you see that preseated necks seat easier, keep in mind that this is all the tension you will & should have. So if you oversize necks, then you end up with higher seating forces, and higher variances in that, affecting OAL.

 

[bigedp51]

Increased seating force can also happen if you wet tumble with SS media or remove the carbon from inside the case neck. Add this to insufficient/improper inside neck chamfer/deburring and the seating force will increase.

After wet tumbling I trim the cases and chamfer and before sizing dip the case necks in powdered graphite. Graphite is nothing more than very fine carbon and the expander will recoat the inside of the case neck..

chamfer

Below on the left a over wet tumbled case mouth and on the right a brand new untouched factory case. Both cases have peened case mouths and need trimmed and chamfered.

Many reloaders when loading bulk .223/5.56 cases on a progressive press use a Lyman type expander. They bump the case mouth onto the .226 diameter part of the expander to ease seating and reduce neck runout during seating.

Bottom line, powdered graphite and using a VLD (very low drag) chamfer/reamer works wonders.

Also a simple case neck thickness gauge will tell you a good deal about the quality and uniformity of your cases. With one turn of the wrist the cases can be sorted on this gauge. I sort my .223 cases this way and the case necks with excessive neck thickness variations are used for blasting ammo in my AR15 rifles.

Case-Neck Chamfer Tools — Pick Your Angle
http://bulletin.accurateshooter.com/2015/08/case-neck-chamfer-tools-pick-your-angle/

 

[243winxb]

I have never lubed or needed to lube inside the case neck before seating bullets

The unlubed expander may have dragged brass from the shoulder, into the neck?
A donut may have formed at the neck, shoulder junction?

Measuring a loaded round , at different places on the neck, may provide a clue.

My guess.

 

[Full Curl]

Thanks for all the great replies! These cases were once fired Nosler cases. They have never been annealed, I typically anneal after 3 firings. I'm not sure how I would be oversizing necks since I'm just using the Foster FL die set as they instruct...? In addition to lubing the outside of the case, I usually run my finger across the edge of the mouth with a tiny bit of lube before putting the case in the press for sizing so the expander ball should be getting lubed as well when it enters and exits the mouth. Maybe I should lube the ball itself before sizing as well...??? I haven't noticed any hard pressure sizing issues when sizing cases on the press...? I don't have a neck wall thickness measuring tool, but may have to look into that.

 

[Full Curl]

Increased seating force can also happen if you wet tumble with SS media or remove the carbon from inside the case neck. Add this to insufficient/improper inside neck chamfer/deburring and the seating force will increase.

This might be it. I do wet tumble with SS media after every firing. I have a VLD chamfer and also outside deburer but usually only use these after trimming. I do not trim after every firing/cleaning. I trim about every third firing when I also anneal, sooner if I need to but it's after the third firing most of the time.

QUESTION - with the peened case mouths photo you inserted, as long as you were still under COAL with the fired case and there was not much variation from one fired case to the next, could you just FL size the fired case and then chamfer and debur the mouth before seating? I did not do this. Since these cases were only on their second firing, I wet tumbled with SS media, FL sized, and seated.

Thanks again for all the information. Always learn something new on here.

 

[Remmy700]

I also wet tumble and it can rough up case necks pretty good. I started just popping primers out and wet tumbling. Then I will size and trim. This typically will clean up the case mouth defects and then chamfer. I now turn necks on every thing I reload and use neck sizer with bushings and no expander. I do have a body die when I need to bump shoulders but very rarely use them. The one biggest thing I have learned in reloading is neck tension is one of the most important elements in consistent accuracy. Honesty the only way u can control that is by bushings and neck turning. When done correctly when U seat a bullet ever single load feels the exact same and u can really feel it on the co-ax. Even high end brass has bad batches and even worse is when people buy to different lots and combine. Best of luck brother

 

[Mikecr]

I'm not sure how I would be oversizing necks since I'm just using the Foster FL die set as they instruct...?

You should engage YOURSELF in this. Consider YOUR results in this.

 

[Full Curl]

I also wet tumble and it can rough up case necks pretty good. I started just popping primers out and wet tumbling. Then I will size and trim.

This is exactly what I do, except that I will not trim, chamfer, and debur unless I'm over recommended COAL. I'm thinking I should chamfer and debur at a minium now.

 

[Remmy700]

Absolutely. I have never got brass out of my tumbler and case mouths not roughed up from media.

 

[Full Curl]

I load mostly for field hunting ammo so have stayed away from neck sizing. I also have not neck turned, maybe something I should look into. I agree with you how important neck tension is. Typically I can get pretty consistent neck tension using quality brass and good FL sizing technique while annealing every 3rd firing. Thanks for the comments.