CNC and steel hardness on shotgun receivers

[bluelynx]

I have been told CNC produced shotgun receivers require softer steel.

Is there an element of truth in the above assertion?

Would this softer steel significantly affect the life of an otherwise well made shotgun?

Just wondering. I know there a few guys on this site that know stuff about metal.

Thanks.

 

[macds]

ZERO truth to that.
If anything, CNC machining can produce a superior product in ultra hard and durable materials.

I routinely hard machine toolsteels upwards up 62 Hrc.

More expensive, YES.

EDIT:
Unless its straight cast, or forged from a work hardening material, and has features that are not machinable.
Sharp internal corners can be next to impossible to machine, unless utilizing EDM, but this applies to soft AND hard materials.


Its up to the design'geneer or toolmaker to know how to best make a quality product as easily as possible.

 

[FLYBYU44]

One of my single shots has a aluminum reciever. Has literally thousands of 3" steel BB loads through it with no ill effects.

 

[bluelynx]

ZERO truth to that.
If anything, CNC machining can produce a superior product in ultra hard and durable materials.

I routinely hard machine toolsteels upwards up 62 Hrc.

More expensive, YES.

EDIT:
Unless its straight cast, or forged from a work hardening material, and has features that are not machinable.
Sharp internal corners can be next to impossible to machine, unless utilizing EDM, but this applies to soft AND hard materials.


Its up to the design'geneer or toolmaker to know how to best make a quality product as easily as possible.

Thanks Macds:

Just how close can CNC machining get to a finished product on an over and under or a side by side receiver? After a CNC receiver job has finished on a receiver, is there still a fair amount of fine tuning and tweaking on manual equipment to meet specifications?

 

[Blastattack]

Thanks Macds:

Just how close can CNC machining get to a finished product on an over and under or a side by side receiver? After a CNC receiver job has finished on a receiver, is there still a fair amount of fine tuning and tweaking on manual equipment to meet specifications?

With enough attention, a CNC can make every single part within 0.001" of the blueprint quite readily. On a mass produced firearm, the amount of final fitting will be none at all, just assembly.

 

[Dad003]

With enough attention, a CNC can make every single part within 0.001" of the blueprint quite readily. On a mass produced firearm, the amount of final fitting will be none at all, just assembly.

More like .0001 and some goes even more accurate ,

I machined everyday bearing parts that are hardened with ceramic , there all kind of tool around for all kind of job , firearms aren't hard to make

 

[ambishooter]

NO. But material should have a high carbon content and heat-treated for durability. Just like a 1911 pistol frame, it is machined out of forged/untreated ordnance steel. Once the final machining is done, heat-treatment begins. After achieving desired temperature exposure, it has to cool down to keep the desired hardness by quenching (submerged into a mineral oil bath), and finished to desired measurements (minor fitting as prior to heat treatment, dimension is almost to tolerance) . If the metal is over-hardened (pardon me for the terminology as I am trying to keep as less technical as possible), the frame/receiver can be brittle and shatter when exposed to severe pressure or movement. High-carbon steel are the ones used in receivers/frame of firearms. But, it has to undergo proper heat treatment so as not to compromise the hardness as required by the purpose. If the material is under the desired hardness, premature wear will occur. But if the material is over-hardened, the risk of shatter is highly likely. Alloys can also be heat-treated to a certain degree.

I have been told CNC produced shotgun receivers require softer steel.

Is there an element of truth in the above assertion?

Would this softer steel significantly affect the life of an otherwise well made shotgun?

Just wondering. I know there a few guys on this site that know stuff about metal.

Thanks.