Lapua 260 brass...problem or not?

[Jointshooters]

Got a box of 260 Lapua brass and started preparing to load some of it the other day. I noticed a few necks were slightly deformed, no problem, I normally run new brass through a Lee Collet die anyway for uniformity.

I encountered a fair bit of resistance lowering the collet die onto the Lapua brass; its like the decapping pin in the die was working the neck out a bit. I didn't lube the brass, as I never lube brass when using the collet die.

Yeah I know Lee dies aren't the best, but its what I've got, they work well for my purposes, and I haven't experienced similar issues with new RP or Nosler 260 brass or with Lapua 223 brass and a 223 Lee Collet die.

Anybody experience similar issues?

 

[turbo54]

Re: Lapua 260 brass...problem or not?

I've not dealt with the 260 brass, but have experienced the deformed necks with their 308 and 338 brass. Honestly, textbook procedure is to run them each through an expander die to work that out. However, I've had great accuracy just seating a bullet into the slightly deformed neck.

 

[jrob300]

Re: Lapua 260 brass...problem or not?

I ran my Lapua .260 brass over an expander ball in a Redding FL die, pressed primer, dropped powder, seated bullets and was shooting .3-.4" groups.

You might try an expander ball instead of the Lee die. It's intended to be inserted into expanded brass and may have too much drag for necked brass.

John

 

[Jointshooters]

Re: Lapua 260 brass...problem or not?

Okay, another question...

Loaded up some of my new 260 Lapua brass Monday and took it to the range yesterday. I ran 5 pieces through the Lee Collet die, 5 pieces partially into a FL die to take dings out of the neck...and the rest I simply seated the bullet. Bullets seemed "hard" to seat in these cases, presumably because they had quite a bit of neck tension.

Shooting a moderate load that has worked well for me in RP and Nosler brass before (123 A-Max and 39.3gr Varget with WLR primer), I experienced pancaked and slightly cratered primers. Some of the primers actually looked like they had slightly backed out, and I had major gas leakage around the primer on one piece of brass (hotter load, 140 A-Max and 38.0gr Varget) that I will likely discard.

Would higher neck tension lead to pressure signs on a load that has been just fine in weaker RP brass?

If so, any way to prevent this in new brass short of running all the brass through a die?

Try some BR2s or CCI-200s?

 

[jagged77]

Re: Lapua 260 brass...problem or not?

Yes I've had similar issues with brand new .260 brass. I do the same thing as with new brass, just run them through an expander ball or Lee Collet die to uniform the neck. I found this brass to be really stiff and had a lot of case neck tension on seating. On second sizing however everything is how it should be.

On the primer issue I've had the same with the .260 Lap brass but only when seated out into the lands and only then when I got a couple wet.

 

[dar1246]

Re: Lapua 260 brass...problem or not?

If the brass is slighty thicker. You may need to change the neck size from a .288 to .290 (for example) to achieve the same neck tension. A standard die may not be the right choice for the brass. Just a thought. good luck
On the expander ball I sometimes smooth the ball so it doesn't hang up in the neck and is a smooter die. This is with RCBS dies.

 

[FCS]

Re: Lapua 260 brass...problem or not?

What is neck diameter of your chamber?

Loaded RP neck diameter runs from 0.291 to 0.293, using a micrometer, depending on lot#.

Loaded Lapua neck diameter is 0.295, using micrometer, very consistantly with limited testing I've been able to do.

Plenty of custom 260 reamers with 0.295 neck.

If your chamber has a neck diameter of <0.298 the brass is unable to expand enough to cleanly release bullet and you will get pressure signs. Next time you fire some rounds loaded with Lapua brass, ease fired brass out of chamber making sure not to ding neck on bolt raceway.

Using this piece of brass, see if you can easily slide a bullet into neck. If you can, you have enough clearance to run Lapua brass w/o neck turning. If you can NOT get bullet to easily slide into neck, you will need to neck turn Lapua brass before using it in your current chamber.

Best guess without having your rifle in hand is that you do not have enough clearance in your current chamber.

Neck tension is not going to give you pressure signs like you are describing.

 

[supratt96]

Re: Lapua 260 brass...problem or not?

Since Lapua brass is a little thicker than other brands, it has slightly less interior volume. This means, with all other things being equal, you will see higher pressure (and higher velocity) with Lapua brass. My Lapua loadings run about 40 fps faster than with Remington brass. Again, so long as all other things are equal.

Also, as previously mentioned, dies that were set up to work with Remington or other similar thickness brass will load higher neck tention with Lapua brass. I use a Redding S type die and use a .292 bushing with Lapua brass and a .288 bushing with Remington.

Hope this helps.

 

[FCS]

Re: Lapua 260 brass...problem or not?

Good point Lakeway.

One does need to reduce powder charge when using Lapua vs. RP if you want to get same velocity. I'll have to check my chronograph/load data log book to confirm but want to say with 140s and H4350 it is about 0.7gr less in Lapua than RP.

I have no personal experince with Nosler 260 brass so unable to comment on needed powder reduction.

 

[Jointshooters]

Re: Lapua 260 brass...problem or not?

Thanks so much for the info, FCS & Lakeway...I'm definitely still learning this reloading thing.

I'll measure loaded & once-fired Lapua brass once I get home and see what the measurements turn out to be, as well as checking the "bullet fit" test. I really want to use Lapua brass, but neck-turning is a non-starter for me at this point because of time.

Looking at my data, it appears that I too am getting 40fps more velocity from Lapua brass vs. the same loads in Nosler or RP brass.

 

[Jointshooters]

Re: Lapua 260 brass...problem or not?

My barrel's chamber is spec'd to .298...measuring fired Lapua and Nosler brass on a set of dial calipers, I get a fairly consistent .297 on the necks of both.

I can slide a bullet without any resistance into the neck of 3x fired Nosler brass; a bullet fits easily into 1x Lapua necks though there does seem to be some very slight resistance.

 

[FCS]

Re: Lapua 260 brass...problem or not?

Drop your powder charge 0.5 to 0.7 gr to get same velocity as loads using Nosler/RP brass.

If you still see high pressure signs, you do not have enough clearance in chamber for neck to expand enough for brass to release bullet.

 

[bchibb]

Re: Lapua 260 brass...problem or not?

I run them thru a full length die and they seem OK. Is this wrong?

 

[Jointshooters]

Re: Lapua 260 brass...problem or not?

Virgin Lapua brass necks measured .290 on my calipers; after running through a Lee FL die they measured .294 and they still measured .294, maybe .295 after a bullet was seated.

Fired 27 rounds today that I ran through the FL die prior to loading, and did not experience any of the pressure signs exhibited in my 10/5 post.