Chambering Issue When Neck Sizing Lapua Rem 260 Cases

[Compact45]

OK, I'm reaching out because I'm out of ideas.

When I neck size my Lapua 260 Rem brass with a redding nonbushing die after firing the cartridges they will chamber in the same rifle without a bullet seated...but, after I seat a bullet (Scenar 139g @ 2.80 col) it will not chamber far enough for the bolt to engage and close and a little force is needed on the bolt to extract the cartridge. IF, however, I full length resize the same brass and seat the same bullet the bolt will close.

What can I check or do differently.

Please stop the head banging from frustration...

Let me know if more info is needed.

Thanks!!!

 

[Sniper260]

Take one of your seated rounds from neck sizing only and get a marker and blacken up the bullet from in front of the ogive to the case mouth/start of the brass..... then chamber it/ extract it and see if you get markings from the bullet getting pushed into the lands... that would cause the hard to close hard to open problem. Try that and let's check so we can find out if yes the bullet is seated too long... or rule seating length out completely...

 

[Sniper260]

It's not heard of enough but a 260 remington chamber isn't exactly set up to shoot 139/140 grain bullets best.... it's made for 120s and 130s... The chambering that is correct and made just for 139 and 140 bullets is called a 260 tactical.... it has a slightly longer throat is the difference...

 

[Compact45]

Ducks,

I did the marker test on a neck sized cartridge and I am seeing marks where the shoulder and body meet. Could the seating operation be pushing the shoulder down enough to prevent it from chambering?

I have a OAL gauge and there is .050 - .055 before the bullet touches the lands.

As I mentioned earlier the cartridge chambers when the case is FL sized but not NK sized.

 

[shoot4fun]

Shouldn't make any difference. You are seating the bullet same in both neck and FL sized brass?

 

[shoot4fun]

Ducks,

I did the marker test on a neck sized cartridge and I am seeing marks where the shoulder and body meet. Could the seating operation be pushing the shoulder down enough to prevent it from chambering?

I have a OAL gauge and there is .050 - .055 before the bullet touches the lands.

As I mentioned earlier the cartridge chambers when the case is FL sized but not NK sized.

If what I think you're asking is correct then you have the neck die set up wrong. The neck die should only size the neck and nothing else should move.

 

[mdmp5]

I was originally gonna suggest that your chamber is tight in the neck, so when inserting a neck sized case w/o a bullet, it chambers. But with a bullet seated, the neck expands a bit, and doesn't chamber. However, you say that f/l sized rounds do chamber. I have to sit down and brainstorm this for a while.

In the meantime, the example you provided lends more credibility to the argument that neck sizing only is an antiquated method that not only affords no advantages, but adds problems. In the meantime, why don't you just put the neck die back in the box and start powering some rounds out with the f/l die? F/L sizing is the way to go, in my opinion. I tried neck sizing only for a while when I first started loading, and it did nothing for me, other than cause some tight bolt closures. My f/l ammo always matched or outshot it, and never had chambering issues.

 

[mdmp5]

If what I think you're asking is correct then you have the neck die set up wrong. The neck die should only size the neck and nothing else should move.

His problem is not originating from the neck sizing operation according to his observations, because he can indeed chamber a neck sized piece of brass. Also, it is hard to set up a neck die incorrectly, other than not screwing it down enough, but this is not the case, since he is seating bullets in the sized cases.

 

[Compact45]

Shouldn't make any difference. You are seating the bullet same in both neck and FL sized brass?

Yes, the same seating die is used, Redding Comp Seating Die.

 

[Doc68]

Make sure you are NK sizing completely. I turn my die down till it's about flush with the lift where the brass goes. Then I turn die 1 more full turn. I was having same issues.

 

[Compact45]

Make sure you are NK sizing completely. I turn my die down till it's about flush with the lift where the brass goes. Then I turn die 1 more full turn. I was having same issues.

Were you able to chamber an empty NK sized case? My NK sized case will chamber without a bullet but after the bullet is seated it will not chamber the NK sized cartridge.

 

[mdmp5]

Compact45, just for the hell of it, can you try seating a bullet a little deeper, like .02" more in the case that was neck sized and see if it chambers? I know that you said your f/l rounds chamber at your length, but if you cannot chamber a neck sized round after seating, then we can at least try to narrow down where the infraction is taking place for certain. As it stands, I am having a hard time devising a plausible model for your observations.

 

[Doc68]

Were you able to chamber an empty NK sized case? My NK sized case will chamber without a bullet but after the bullet is seated it will not chamber the NK sized cartridge.

Yes I was able to chamber the case only. Once I seated bullet it would be an effort to close bolt. Even forced it one night and it got stuck. Took a few smacks with a mallet to get it out. Will never do that again.

I even tried to seat bullet further in and to no avail. Once i adjusted my NK die I haven't had any issues.

 

[Compact45]

Yes I was able to chamber the case only. Once I seated bullet it would be an effort to close bolt. Even forced it one night and it got stuck. Took a few smacks with a mallet to get it out. Will never do that again.

I even tried to seat bullet further in and to no avail. Once i adjusted my NK die I haven't had any issues.

I tried doing this but I'm reloading on a Dillon 550 and can not get the extra 1 full turn after the die is flush.

I am about .09 -.10 away from chambering a cartridge that is NK sized with bullet seated. Crude measurement but just a point of reference.

 

[Compact45]

Compact45, just for the hell of it, can you try seating a bullet a little deeper, like .02" more in the case that was neck sized and see if it chambers? I know that you said your f/l rounds chamber at your length, but if you cannot chamber a neck sized round after seating, then we can at least try to narrow down where the infraction is taking place for certain. As it stands, I am having a hard time devising a plausible model for your observations.

mijp5, tried .05 deeper but nojoy. Seems to be stopping on the shoulder/body junction.

 

[shoot4fun]

Were you able to chamber an empty NK sized case? My NK sized case will chamber without a bullet but after the bullet is seated it will not chamber the NK sized cartridge.

If he had it screwed down so far somehow that it was crushing the shoulder that would do it.

 

[Sniper260]

Ducks,

I did the marker test on a neck sized cartridge and I am seeing marks where the shoulder and body meet. Could the seating operation be pushing the shoulder down enough to prevent it from chambering?

I have a OAL gauge and there is .050 - .055 before the bullet touches the lands.

As I mentioned earlier the cartridge chambers when the case is FL sized but not NK sized.

I was looking for marks on the bullet itself right there on the ogive, not the brass... If you have marks on the bullet that means they are loaded too long and and getting pushed into the lands when you try to chamber a round... seat the bullet a tad deeper and re try...

If you are getting marks on the brass itself on the sholder... your die may be set up wrong and be too deep in the press.

 

[Sniper260]

Post pics.... helps a lot more..

 

[shoot4fun]

I do agree about putting the neck sizer away. Buy yourself the tools to properly measure headspace so you can set the FL sizer up properly. FL size to bump the shoulder back one to one and a half thousandths every time and be done with it.
Still, what you are describing makes no sense. It is something I would have to put my old eyes on to figure out for sure.

 

[mdmp5]

mijp5, tried .05 deeper but nojoy. Seems to be stopping on the shoulder/body junction.

Ok, the seating is imparting a very small amount of change of shape of the case, likely near the shoulder/neck junction. I cannot tell exactly what is happening, but you are using a die without a bushing, which means that the entire neck is being sized; a bushing die leaves a visible portion of the lower neck unsized. A fire formed case already doesn't have much wiggle room in the chamber, so the slightest deformity can impeded it from chambering. You are simply in need of a f/l sizing. Knock the shoulder back and it will work, hopefully for the next 2-3 firings with the neck die only. However, as I stated above, I am pro f/l sizing every time. So if i were you, I would consider just going with the f/l die by itself.

 

[mdmp5]

If he had it screwed down so far somehow that it was crushing the shoulder that would do it.

I was looking for marks on the bullet itself right there on the ogive, not the brass... If you have marks on the bullet that means they are loaded too long and and getting pushed into the lands when you try to chamber a round... seat the bullet a tad deeper and re try...

If you are getting marks on the brass itself on the sholder... your die may be set up wrong and be too deep in the press.

The only thing about this explanation that doesn't work is that he was able to chamber a neck sized case without the bullet.

 

[Unknown]

When unloaded and sized cases chamber easily, but loaded cases with a bullet won't chamber easily, I would look for the following:

1. Check to see if the bullet is being jammed into the lands by smoking/dykem the bullet and looking for the lands marking the ogive of the bullet.

2. See if the cases are too long. If the neck is too long for the rifle's neck allowance, then when the bullet is in the case, the excess neck material ends up attempting to crimp onto the bullet, thereby making chambering difficult.

3. See if the neck diameter of your loaded rounds is larger than the chamber. If your case necks have thickened, then when the bullet is in the neck, the neck portion of the chamber can't squeeze the neck down.

Measure the outside diameter of fired cases, and check that against the diameter of your loaded rounds. You will be able to tell if the necks are too big for the chamber. Remember to allow for a little spring-back on the fired cases.

 

[Doc68]

Ok put just your shell holder in the part that goes up to the die. Bring it all the way up. Then start screwing your die into the press. When your die touches the shell holder, let the part that goes up to meet the die go down all the way. Then screw the die in one more full turn. That should be correct. If that doesn't help then I'm lost.

 

[Compact45]

I do agree about putting the neck sizer away. Buy yourself the tools to properly measure headspace so you can set the FL sizer up properly. FL size to bump the shoulder back one to one and a half thousandths every time and be done with it.
Still, what you are describing makes no sense. It is something I would have to put my old eyes on to figure out for sure.

What tool do I need for measuring headspace? I'm guessing a tool that measures the shoulder.

 

[Compact45]

Ok, the seating is imparting a very small amount of change of shape of the case, likely near the shoulder/neck junction. I cannot tell exactly what is happening, but you are using a die without a bushing, which means that the entire neck is being sized; a bushing die leaves a visible portion of the lower neck unsized. A fire formed case already doesn't have much wiggle room in the chamber, so the slightest deformity can impeded it from chambering. You are simply in need of a f/l sizing. Knock the shoulder back and it will work, hopefully for the next 2-3 firings with the neck die only. However, as I stated above, I am pro f/l sizing every time. So if i were you, I would consider just going with the f/l die by itself.

I'm beginning to move toward the FL light after this. I pulled about 75 reloads. Glad it wasn't more!!!

 

[shoot4fun]

What tool do I need for measuring headspace? I'm guessing a tool that measures the shoulder.

This is what I use.

headspace measure tool at Sinclair Inc

 

[Compact45]

When unloaded and sized cases chamber easily, but loaded cases with a bullet won't chamber easily, I would look for the following:

1. Check to see if the bullet is being jammed into the lands by smoking/dykem the bullet and looking for the lands marking the ogive of the bullet.

2. See if the cases are too long. If the neck is too long for the rifle's neck allowance, then when the bullet is in the case, the excess neck material ends up attempting to crimp onto the bullet, thereby making chambering difficult.

3. See if the neck diameter of your loaded rounds is larger than the chamber. If your case necks have thickened, then when the bullet is in the neck, the neck portion of the chamber can't squeeze the neck down.

Measure the outside diameter of fired cases, and check that against the diameter of your loaded rounds. You will be able to tell if the necks are too big for the chamber. Remember to allow for a little spring-back on the fired cases.

1. No mark on the bullet. Mark showed on the shoulder.body union.
2. Cases are trimmed.
3. All measurements taked at the case mouth on the outside.
Fired .292
FL Sized .291
NK Sized .292
FL Sized w/Bullet Seated .293
NK Sized w/Bullet Seated .2935

I should have mentioned earlier, this rifle is a GAP and chambered prior to Lapua releasing 260 Rem brass. Not sure if that makes a diff.

 

[armorpl8chikn]

Is it any wonder some of the voices of sanity have quit posting here. Out of all that pea cooling bloviating one poster had the balls to tell him what is really causing his problem.
Keep backing that 60 year old nag called neck sizing guys, she may run a decent race yet. <eyeroll></eyeroll>

 

[17874]

What size neck bushing are you using? If you use one too small it could possibly cause your problem.

I would also make sure your neck sizing die is set up right. I would measure everything from the neck down, before and after neck sizing.

 

[17874]

Can you provide three dimensions?

Size of neck on fired case.

Size of neck on loaded round.

Size of neck after neck sizing.

 

[Compact45]

Can you provide three dimensions?

Size of neck on fired case.

Size of neck on loaded round.

Size of neck after neck sizing.

All measurements taked at the case mouth on the outside.
Fired .292
FL Sized .291
NK Sized .292
FL Sized w/Bullet Seated .293
NK Sized w/Bullet Seated .2935

 

[Compact45]

Is it any wonder some of the voices of sanity have quit posting here. Out of all that pea cooling bloviating one poster had the balls to tell him what is really causing his problem.
Keep backing that 60 year old nag called neck sizing guys, she may run a decent race yet. <eyeroll></eyeroll>

What is really causing my problem I may have missed it. Do you mean to FL size and bag the NK sizing?

 

[hewlett260]

Bump the shoulder or full length size every time. Problem solved. Then sell the neck sizer and use the cash for another box of bullets.

 

[Compact45]

Bump the shoulder or full length size every time. Problem solved. Then sell the neck sizer and use the cash for another box of bullets.

Roger that!!! Thanks.

 

[17874]

Chambering Issue When Neck Sizing Lapua Rem 260 Cases

All measurements taked at the case mouth on the outside.
Fired .292
FL Sized .291
NK Sized .292
FL Sized w/Bullet Seated .293
NK Sized w/Bullet Seated .2935

You need to turn your necks. There isn't enough room in your chamber for the neck to expand and release the bullet properly. I have to do the same thing. For example, my loaded rounds measure .293 and fired casings measure .295. If a loaded round measured .296 than I would have a hard time getting it to chamber.

Lapua brass usually has .015 wall thickness at the neck. If you turn it down to .013 or .012 thickness, I bet all your problems will go away. If you want to send me a piece of brass, I will turn it for you and you will know for sure.

.292 at the neck for a fired case is really tight. If I were a betting man, you are deforming your shoulder trying to push the oversized neck (with bullet seated) into your chamber.

 

[armorpl8chikn]

You need to turn your necks. There isn't enough room in your chamber for the neck to expand and release the bullet properly. I have to do the same thing. For example, my loaded rounds measure .293 and fired casings measure .295. If a loaded round measured .296 than I would have a hard time getting it to chamber.

Lapua brass usually has .015 wall thickness at the neck. If you turn it down to .013 or .012 thickness, I bet all your problems will go away. If you want to send me a piece of brass, I will turn it for you and you will know for sure.

.292 at the neck for a fired case is really tight. If I were a betting man, you are deforming your shoulder trying to push the oversized neck (with bullet seated) into your chamber.

Except when he FL sizes using same brass same bullet he has no problem. This clearly illustrates it has nothing to do with his neck thickness. I shot many hundreds of rounds through a tight chamber when I was shooting 1000yd BR, with .002 expansion clearance with no problems, lots of shooters do this. The only chambering problems I have ever had stemmed from using neck sizing dies.

Throw the neck sizing die away so no one else will ever have this problem again. FL size with the die set up to bump the shoulder one or 2 thousanths and your problems will go away and your ammo will be just as accurate, if not more so.

 

[Compact45]

Except when he FL sizes using same brass same bullet he has no problem. This clearly illustrates it has nothing to do with his neck thickness. I shot many hundreds of rounds through a tight chamber when I was shooting 1000yd BR, with .002 expansion clearance with no problems, lots of shooters do this. The only chambering problems I have ever had stemmed from using neck sizing dies.

Throw the neck sizing die away so no one else will ever have this problem again. FL size with the die set up to bump the shoulder one or 2 thousanths and your problems will go away and your ammo will be just as accurate, if not more so.

I have a tool ordered so I can measure the shoulder bump with my FL sizer. After going to the range and finding 75 rounds that would not chamber I'm going FL now. During my reflection of WTF happen I thought my groups didn't change between FL versus NK sizing any way. I was only NK sizing to "save to Brass" some. But, with proper shoulder bump from a FL die I'm hoping to get the same brass savings.

Any benefits on switching to a FL bushing sizer?

Learning something new daily is what keeps this interesting.

p.s. After I pulled the bullet from the NK sized case and chambered the empty case again it would chamber with just a slight "little" more push. Previous fired unsized cases would chamber too.

 

[Unknown]

Is it possible that something during bullet seating is causing the shoulder of the case to bulge just a tiny bit? I used to have that problem with some 5.56 ammo, and often it was so subtle I couldn't see the bulge, but the rounds wouldn't chamber. Maybe check the case diameter where the bottom of the shoulder meets the body of the case.

If continual experimentation and evaluation doesn't lead you to the cause, I would be likely to go to a full length die, just so I could get back to shooting. Over time, maybe the problem will show itself. I think this site, or a bench rest reloading forum would be the places to go for answers. It sure seems like you are getting enough info that you should be close to finding the cause.

 

[17874]

I have a tool ordered so I can measure the shoulder bump with my FL sizer. After going to the range and finding 75 rounds that would not chamber I'm going FL now. During my reflection of WTF happen I thought my groups didn't change between FL versus NK sizing any way. I was only NK sizing to "save to Brass" some. But, with proper shoulder bump from a FL die I'm hoping to get the same brass savings.

Any benefits on switching to a FL bushing sizer?

Learning something new daily is what keeps this interesting.

p.s. After I pulled the bullet from the NK sized case and chambered the empty case again it would chamber with just a slight "little" more push. Previous fired unsized cases would chamber too.

Do yourself a huge favor and call GAP to get the neck dimensions on the reamer they used to chamber your rifle. Without a doubt, it is a match reamer and smaller than SAAMI spec, which means you should turn the necks on Lapua brass.

I get that it will chamber FL sized rounds and not neck sized rounds, but a smaller expander ball in the the FL die could do this.

If the neck on a fired case measures
.292, FL sized loaded round .293, and neck sized loaded round .2935 that means you should turn your necks. The neck on a loaded round should measure slightly smaller than the neck on a fired casing.

 

[Compact45]

Do yourself a huge favor and call GAP to get the neck dimensions on the reamer they used to chamber your rifle. Without a doubt, it is a match reamer and smaller than SAAMI spec, which means you should turn the necks on Lapua brass.

I get that it will chamber FL sized rounds and not neck sized rounds, but a smaller expander ball in the the FL die could do this.

If the neck on a fired case measures
.292, FL sized loaded round .293, and neck sized loaded round .2935 that means you should turn your necks. The neck on a loaded round should measure slightly smaller than the neck on a fired casing.

I will contact GAP for some info, might IM George from the forum. Hope they keep records from prior builds.

 

[Sniper260]

Get a different brand piece of bras and neck size it only... I bet it fits.. neck is what my next guess was but I didn't get to this thread until now... yep I agree with the above... The lap a brass is thicker and it's probably the problem... Easy to solve too.... sell it and get nobler brass to run... I hear it's good brass... The lap a brass you will have to neck turn...

you can do the old marker trick again on the neck of the brass too to see if it scratches off any...

 

[tolnep]

i had a similar problem and i have read about someone else a few months back that had the same problem. 260, SAAMI specs, lapua brass. some wound chamber and some were very hard t chamber. Yet the bullet did not touch the lands, the shoulder was bumped back and everything measured up to that point (lengths to various parts of the case were per book).

then i got a ball mike and it turns out some of my cases were a bit thicker at the neck top than the bottom. size, insert bullet and the bullet would push the neck out just enough to make it very hard to chamber. i got a kit and started turning my necks. The goal was to simply take off the 'extra' not to turn it way down. goal was .015 thickness. when is stated doing this, a lot of metal came off the very top of the neck and little anywhere else. and the resulting rounds chambered with ease.

drove me crazy because the bullet was a good bit off the lands, the shoulder was in spec and the full length was in spec. this was not something that occurred on all my lappua brass. i think some of the lots had issues. the other guy that had the same issue purchased his cases about the same time i bought a couple of boxes.

 

[thespecialist]

I agree with the guys above that it sounds like you're going to have to turn the necks on that Lapua brass. You don't need to take off much, maybe turn the necks down to .0135-.014" which is the same as RP 260 brass. Just be aware that sooner or later as the material flows up from the shoulder it will have to be done again.

I'll also agree with armorpl8chikn, throw that neck die in the trash and full length size your brass after every firing instead. If possible, get yourself a bushing FL sizer to avoid overworking the necks of your brass as well.Forster, Redding, RCBS all make them and they all work so just grab one and an assortment of bushings and be done. I have at least one from each manufacturer in one caliber or another and they all work the same, so no real need to be particular about which brand you get.

 

[mdmp5]

If he had to neck turn, then why can he chamber f/l sized rounds without an issue?

 

[17874]

If he had to neck turn, then why can he chamber f/l sized rounds without an issue?

Because I bet the expander ball is smaller on the FL Die giving more neck tension and it stretches the neck a bit.

Either way if a fired case measures
.292 he needs to neck turn Lapua brass.

(.015 X 2) + .264 = .294

Fired case measures .292.......... PROBLEM?

Now Lapua brass can differ from lot to lot but on average it has .015 thick neck walls.

 

[mdmp5]

Because I bet the expander ball is smaller on the FL Die giving more neck tension and it stretches the neck a bit.

Either way if a fired case measures
.292 he needs to neck turn Lapua brass.

(.015 X 2) + .264 = .294

Fired case measures .292.......... PROBLEM?

Now Lapua brass can differ from lot to lot but on average it has .015 thick neck walls.

If you impart .001 neck tension or .006 neck tension, it makes no difference in the OD of the case neck with a bullet seated. That is why if his f/l sized rounds chamber, but neck sized rounds don't, I would not implicate neck thickness as the culprit. I originally thought that was his problem, but when he said f/l sized rounds chamber, I tried to look elsewhere.

 

[BLDTYLRY]

What bullet are you running to go from a .292" OD to a .2935" OD using Lapua 260Rem brass?

I'm running 140gr A-max and the OD is .296" with Lapua Brass and my neck is reamed to .297"; I shoulder bump and neck size to .294".

If you have a fired neck OD of .292" and a loaded round pf .293" +/- .0005" then you are going to need to neck turn. If this is not the case, then how is it that your fired necks get smaller?

 

[17874]

If you impart .001 neck tension or .006 neck tension, it makes no difference in the OD of the case neck with a bullet seated. That is why if his f/l sized rounds chamber, but neck sized rounds don't, I would not implicate neck thickness as the culprit. I originally thought that was his problem, but when he said f/l sized rounds chamber, I tried to look elsewhere.

We will have to agree to disagree. Either way he has to turn the necks on Lapua brass.

 

[ColoYooper]

I have the same setup, shooting Lapua 260 brass. I ran into a similar problem where my brass grew 0.008" beyond spec. My 260 chamber has a ramp, not a straight wall where the case ends and the throat begins. Placing a neck-sized, but empty case into the chamber was not a problem because the neck was several thousands smaller in diameter and the too long neck could extend into the ramp. Once I seated a bullet into the neck, it expanded the neck diameter and it struggled to chamber...I could chamber...but the increased "crimping" of the neck caused me to flatten primers significantly. Full length re-sizing helped, but the solution for me was the trim the cases back to spec. NOTE: I think the Lapua brass is a bit softer than others and appears to need trimming more often.

 

[6.5 GUY]

I will contact GAP for some info, might IM George from the forum. Hope they keep records from prior builds.

I just spoke to George about this subject a week ago. It seems some older GAP rifles will only chamber Remington brass due to the Lapua brass being too thick.

I have a older GAP built on a Surgeon Action I just acquired a few weeks ago in 260 Remington but my measurements are a lot different then yours. My fired Lapua necks measure .296-.297", and loaded rounds measures .294".

Your own measurements should tell you something is wrong if your fired case neck is smaller then a loaded round, because they shouldn't! The fired case should be larger then the loaded round measurement so the case neck can properly release the bullet. From what you're saying your neck dimensions are tighter then normal.

It is odd that the F/L die will chamber vs. the Neck die with a loaded round but those measurements don't work.... you could turn the necks or have GA Precision open up the neck in your chamber, but either way you'll want to resolve that issue.

Hope that helps?