Gunsmithing Reamer for formed 260rem Lake City brass

[Eric32]

Does anyone have a reamer made for necking down Lake City brass to 260rem WITHOUT turning necks.

I would like some advice on reamer specs or where to source one. And any past experiance.

My end goal is to run
123 smks/123 eldm+IMR8208 XBR+ LC brass in my dillon press for a economy rifle.

 

[Steel head]

Just neck up Winchester 243 brass.
Less steps and it’s decent brass
Been using for years.

No need for a custom reamer.

 

[Eric32]

LC is generally much cheaper by the 1000 pack so I can purchase several thousand cases and not worry about getting brass back.

Most 243win brass is bout $40 per 100, bulk lake city is $170 per 1000 from @airborne6.8

 

[DAVETOOLEY]

First form some brass. Seat a bullet and measure the loaded round. You need a minimum .004" clearance in the chamber. A SAAMI chamber has a .299-.298" diameter neck. With thicker necks you may run into sizing problems with standard dies. A bushing FL die will almost certainly be needed.

https://saami.org/wp-content/uploads/2019/02/ANSI-SAAMI-Z299.4-CFR-Approved-2015-12-14-Posting-Copy.pdf

Reamer manufactures that I use.

Manson Precision Reamers | Gunsmithing Tools | Grand Blanc, MI

We're a premier supplier of chamber reamers, headspace gauges, and other cutting and gunsmithing tools for rifles, shotguns, handguns, and other firearms.

mansonreamers.com

Reamers, Chamber Reamers, Jgstools.com, Rifle, Shotgun, Pistol, Chamber Reamers , Gauges, Bore Reamers, Precision Tools www.jgsprecision.com

 

[Greg Langelius *]

All my 260 Rem brass starts as Hornady 7mm-08 brass, necked down to 6.5mm by simply running the case through the F/L resizing die. My 260 Rem chamber is SAAMI Spec.

One trick; back off the die a turn or two, leaving a significant rearward portion of the neck at 7mm-08 case diameter. This is called partial neck resizing and was an early BR technique used before bushing dies were put to use.

This centers the case neck in the chamber. When fired, the soot mark stops dead at the point where the diameter increases, indicating a fully sealed case neck during firing.

Chambering effort is not significantly increased in my SAAMI chamber.

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I use a standard .308 F/L die as a bump die. Only a very little bit of bump is actually needed.

When bumping, a case gauge is essential. Mine is .308 and works for my .260, .308, and 7.62x51 brass.

My .260 Rem rifle is built on a Savage receiver, and the barrel is headspaced using .308 GO gauge.

I go to some extent to ensure that my brass is not excessively resized.

Greg

 

[padom]

I'm running LC 11 brass in my AR 6.5cm. Much tougher and lasts longer than Hornady. I made 500pcs back when Hornady was the only game in town.

I turned my necks though.

 

[Eric32]

@padom

How was the velocity / case capacity of the reformed brass?

@DAVETOOLEY

Is the .004 per side or overall?

@Greg Langelius *

Thanks for the tips

 

[padom]

@padom

How was the velocity / case capacity of the reformed brass?

Velocity is good. Remember I'm shooting it in a gasser so my velocity will be lower than 6.5cm bolt gun loads.

With a 123 Lapua over 42.4gr H4350 out of a 22" Rock Creek Cut rifled barrel I'm getting 2865 SD7 and consistent sub 0.5moa accuracy. It has less case capacity than Hornady for sure because its thicker but I'm on 5 firings and nothing has changed. Pockets are tight and looks great. I do anneal after every firing

 

[Eric32]

I plan on 2900 fps from a boltgun, I also gave the 107smks a look at 3200fps from the rifleshooter.com

6.5 Creedmoor loads: 107 SMK IMR 8208 XBR and 142 SMK Superformance

6.5 Creedmoor loads: 107 SMK IMR 8208 XBR and 142 SMK Superformance 6.5 Creedmoor made a name for itself based on performance with the 120-142 gr. class bullets. Unlike older cartridges such as th…

rifleshooter.com

 

[DAVETOOLEY]

@padom

How was the velocity / case capacity of the reformed brass?

@DAVETOOLEY

Is the .004 per side or overall?

@Greg Langelius *

Thanks for the tips

That's overall. That's the minimum not the max.

 

[FCS]

Does anyone have a reamer made for necking down Lake City brass to 260rem WITHOUT turning necks.

I would like some advice on reamer specs or where to source one. And any past experiance.

My end goal is to run
123 smks/123 eldm+IMR8208 XBR+ LC brass in my dillon press for a economy rifle.

You'll spend more $ chasing the "economy" then buying correct brass out of the gate. BTDT. Best wishes on your adventure.

 

[DAVETOOLEY]

Eric32

PM sent
I have 2 1/2 gallons of once fired brass.

 

[Greg Langelius *]

I'm getting approximately 2850fps w/140 A-Max/142SMK over 43.8gr of H4350, out of a 28" L-W stainless Savage Varmint Contour.

The load is capable of multiple consecutive X's at 1Kyd in actual F Open comp.

Currently (slowly) developing the load for the 143 ELD-X.

The stepped neck diameter allows some attention to concentricity despite the SAAMI neck's larger size. The raised resizing die may also allow the expanded rear of the case to center itself, allowing the case to be supported all around, centered and aligned within the chamber itself.

I believe this launches the bullet straight into alignment with the bore axis. With SAAMI chambers, this may be the full extent of concentricity I can achieve. I have no non-SAAMI chambers.

IMHO, the technique results in the minimum amount of brass working, and the 308 bump die permits the 260 Rem toolhead/die relationships (Dillon RL550b) to remain undisturbed.

My Elder Brother explained to me that the technique predates tight neck chambers and bushing dies, serving somewhat as a precursor approach to solving the same problems, while achieving whatever benefit can be derived without resorting to extra, specialized equipment. I think of it as an answer to the question of what I would be doing if tight necks and bushing dies had never come along.

Greg

 

[Eric32]

@FCS

I dont think so it's the cost of a reamer. Not a big expense.

@DAVETOOLEY

I made some dummy rounds headspace to 2.018 at the .400 datum, I have a loaded neck diameter of .294-.295 which means that I need a .299 neck.

Which means that a SAAMI 260REM reamer has a .299 neck.

 

[FCS]

@FCS

I dont think so it's the cost of a reamer. Not a big expense.

You are missing the point but if it works for you, go for it.
Your $, you are a big kid now and allowed to spend your $ as you see fit.

 

[Eric32]

What is the point that I am not getting?

A SAAMI standard reamer has a .299 neck, a most every good Smith will have one.

LC brass has .294 neck loaded with a 123smk/107smk and imr8208 xbr is right near Varget in burn rate. So I cant see the down side.

 

[stangfish]

Eric, The guy knows his stuff. He has been down this road. My problem is he is talking to you like he is the adult and you are the child. So fuck him. Do it! It's your journey. Live it.

 

[Eric32]

Took the advice under careful consideration, still gonna go thru with it. If she will shot a consistent 1/2 inch at 100 yards, and has a ES lower than 20fps. It will be good enough for PRS.

I won a free chamber from a local Smith at a match just a few weeks ago. So the 8.5 twist rate I had laying around is going to work. Got it silly cheap.

Ran some brass and FL sized it already and gonna see how it all works out.

The lake city is annealed on a AMP so gonna load it when the barrel gets back.

Overall this project is gonna cost around $350. With $100 spent on 1k pieces of LC.