Machinist Mondays

[Defiance Machine]

In this #MachinistMonday we are going to talk about... Sales. Wait!! What???​

More directly, we're also going to talk about CNC programming and how we have connected the two, as it was asked here earlier.

CNC (Computer Numerical Control) programs are written with code that allows a computer to control movements and functions of a machine tool.

A CNC programmer can take a 3D model from a CAD (computer-aided design) program and use CAM (computer-aided manufacturing) software to post code that will control a particular machine to make the part.

Generally, a new program is written for manufacturing each part. If there were variations of that part, there would need to be additional programs written.

If you're the type of company that likes to offer a ton of options and variations, writing a new program for each variation would be a real issue. Enter: Subroutines and Macro programming.

A subroutine is a CNC program, that can be called up from another program. Let's say you're going to machine a complex pocket into several different parts. You write the subroutine once and write one line of code to call it up in each of the programs that require that pocket.

Macro programming is used when you want to incorporate variables, such as different lengths or right and left hand, for example. You can have a single "master" program that is driven by variables that makes 1,000's of different variations of the part. Macro programming also utilizes Logical Functions such as "IF" and "WHILE" to perform functions (machine features) when certain conditions (variables) are true ("EQUAL TO", "LESS THAN", etc.).

We are one of those companies that offers a ton of options, but we also make a high volume of parts. Our proprietary software allows the Sales Dept. to create a file for every action that we sell that sets the variables in the CNC control.

We use macro programming to make countless variations efficiently, giving the customer exactly what they need while keeping the cost down.

 

[ShtrRdy]

Thank You for explaining how the firmware is created to run on a particular machine.

 

[Wannashootit]

Our proprietary software allows the Sales Dept. to create a file for every action that we sell that sets the variables in the CNC control.

One hell of a novel- and efficient- approach.

 

[Defiance Machine]

Stress Kills.

Machinists need to learn how to handle stress, and I’m not talking about the kind you feel when you scrap a part.

Metal has stress and it needs to be considered when you’re trying to machine something to exact specifications including straightness, roundness, and perpendicularity.

It’s like there are springs between the atoms that are pushing or pulling against each other. When material is removed, that allows the metal to move under that strain. A long piece of metal that has not been “stress-relieved” can bow like a banana if you remove a significant amount of material from one side. It’s hard to make precision parts this way.

We do several things to manage stress:

• We machine all critical components such as bolts, receivers, firing pins, cocking pieces, etc. out of pre-hardened aircraft certified steels. These metals have been heat-treated to harden, temper and stress-relieve. If we machined material in the annealed (soft) state then hardened it, it would change shape and dimension.
• We handle the material gently, from off-loading the 12’ bars from the truck to shipping the final product.
• We choose machining methods that do not induce additional stress into the steel such as Wire EDM, rather than broaching.
• We leave mass where we can. Our target actions have custom magazine cuts, heavy rear tangs, and integral scope rails that leave material on the receiver making bowing less likely.
• We are strategic about how we remove material. Techniques such as spiral milling are utilized to avoid removing material from one side before the other.

These tactics keep our finished product straight and true when they come out of the machine and after 100,000 firings.

 

[Edds]

Next Monday, you could show a "start to finish" video of the machines making an action and then sell that action to me.

 

[Davess]

@Defiance Machine

Do you or the installer utilize a Laser Interferometer? Most of the machine tool builders do this at thier factory but not at installation. I think very few shops do this ever.
On a 3 axis machine I will on a rare occasion find one axis that is within tolerance on positioning accuracy when checking with the laser.
Do you utilize a Ball Bar at installation and periodically?

I'm mostly curious which industries are adopting the practices.

Nice machines, They should give excellent service.

We do comps on ours with the Renishaw, working on sett8ng up a dmg more that the guys are creaming on, we have mostly mazak, haas, hurco, hardinge t51 and a few others

 

[nikonNUT]

WOW!

I've only had the privilege to walk through 2 other facilities with that much tooling and equipment to turn hunks of metal into intricate pieces.

One at Boeing and the other at Lockheed Martin.

Keep up the great work!

Worked at Lockheed while the BUFF re-power was in its beginning stages. They brought in shit that still had 50s era dust on it! Big Hufford stretch dies and the like. Great machines! The machine I ran the most was an OLD vertical jig borer. I think that one was PRE WWII!

We do comps on ours with the Renishaw, working on sett8ng up a dmg more that the guys are creaming on, we have mostly mazak, haas, hurco, hardinge t51 and a few others

DMG machines are amazing! To this day this video melts my brain!

And that is 12 year old tech!

 

[Tokay444]

Worked at Lockheed while the BUFF re-power was in its beginning stages. They brought in shit that still had 50s era dust on it! Big Hufford stretch dies and the like. Great machines! The machine I ran the most was an OLD vertical jig borer. I think that one was PRE WWII!



DMG machines are amazing! To this day this video melts my brain!

And that is 12 year old tech!

If you like that, watch Titanium Crown...

 

[The D]

If you like that, watch Titanium Crown...

It’s not super complicated but I like watching chess pieces being machined

 

[Defiance Machine]

Before...

After…​

There are several steps to turning a piece of bar stock into a finished receiver.

It takes a saw, lathes, 4 and 5 axis milling, a hone, wire EDM, and sinker EDM.

This 2 1/8” diameter bar of pre-hardened 416R is used to make stainless receivers with integral recoil lugs and weighs 9.44 pounds. The anTi X receiver has had over 90% of the mass removed and now weighs only 0.9 pounds. And it still includes integral 20 MOA scope mounts and integral recoil lug.

Modern machining and innovative processes allow us to make better, more accurate rifle actions.

 

[kcsmith]

How much total machine time (excluding setups because that can vary between people ) does it take to make the receiver posted above ? 3 hours

 

[Mike at Defiance]

How much total machine time (excluding setups because that can vary between people ) does it take to make the receiver posted above ? 3 hours

The anTi X receiver takes closer to 6 hours of machine time to get to this point from bar stock and still needs to go through laser engraving and vibratory finishing.

 

[srt-4_uk]

So what I'm reading is if I backorder one, it'll ship in about 10hrs...

 

[BuLLet]

You could get the bar stock and save even more time!

 

[Defiance Machine]

​

Here’s a quick look at the steps we take to manufacture a receiver. From being sawed from a 12’ bar of hardened steel to gun drilled, threaded, and faced on a precision CNC lathe. That lathe operator also runs those same receivers in a 5-axis mill and then back into a lathe for OD turning. The bore of the receiver will get honed before it goes to the wire EDM to cut the lug ways. At this point, we call this a “Receiver Blank”. There are several variations with different lengths and bore diameters as well as right and left hand. These are stored in inventory until we print a manufacturing order for the specific action and pull the appropriate blank. Deviant, Rebel, Elite, Ruckus, and anTi X receivers go to our Kitamura 5-axis mills next and are machined to near completion, only needing the sinker EDM for a final cut. Tenacity, Outcast, and anTi receivers are machined in our Nakamura mill-turn centers followed by sinker EDM. These last machining steps are where the customization happens, such as different loading ports, magazine types, and scope base styles. Laser engraving, tumble finishing, assembly and final QC are last, just prior to shipping.

At each of these work areas there are exceptional people that care about and take pride in the quality of product we send to the customer.

 

[Baron23]

​

Here’s a quick look at the steps we take to manufacture a receiver. From being sawed from a 12’ bar of hardened steel to gun drilled, threaded, and faced on a precision CNC lathe. That lathe operator also runs those same receivers in a 5-axis mill and then back into a lathe for OD turning. The bore of the receiver will get honed before it goes to the wire EDM to cut the lug ways. At this point, we call this a “Receiver Blank”. There are several variations with different lengths and bore diameters as well as right and left hand. These are stored in inventory until we print a manufacturing order for the specific action and pull the appropriate blank. Deviant, Rebel, Elite, Ruckus, and anTi X receivers go to our Kitamura 5-axis mills next and are machined to near completion, only needing the sinker EDM for a final cut. Tenacity, Outcast, and anTi receivers are machined in our Nakamura mill-turn centers followed by sinker EDM. These last machining steps are where the customization happens, such as different loading ports, magazine types, and scope base styles. Laser engraving, tumble finishing, assembly and final QC are last, just prior to shipping.

At each of these work areas there are exceptional people that care about and take pride in the quality of product we send to the customer.

Please keep this thread going....love it.

 

[sirhrmechanic]

I know this isn't a CNC machine but I still think it's pretty cool so I took a picture when at work. It's about 4ft thick.View attachment 7848642

Is that a flat plate? Because… wow!

Sirhr

 

[JBoomhauer]

Is that a flat plate? Because… wow!

Sirhr

There’s a decent chance that comes from rock of ages in VT.

 

[sirhrmechanic]

There’s a decent chance that comes from rock of ages in VT.

Yup. It’s a thriving industry down in Barre.

 

[308pirate]

In this #MachinistMonday we are going to talk about... Sales. Wait!! What???​

View attachment 7856723


More directly, we're also going to talk about CNC programming and how we have connected the two, as it was asked here earlier.

CNC (Computer Numerical Control) programs are written with code that allows a computer to control movements and functions of a machine tool.

A CNC programmer can take a 3D model from a CAD (computer-aided design) program and use CAM (computer-aided manufacturing) software to post code that will control a particular machine to make the part.

Generally, a new program is written for manufacturing each part. If there were variations of that part, there would need to be additional programs written.

If you're the type of company that likes to offer a ton of options and variations, writing a new program for each variation would be a real issue. Enter: Subroutines and Macro programming.

A subroutine is a CNC program, that can be called up from another program. Let's say you're going to machine a complex pocket into several different parts. You write the subroutine once and write one line of code to call it up in each of the programs that require that pocket.

View attachment 7856725

Macro programming is used when you want to incorporate variables, such as different lengths or right and left hand, for example. You can have a single "master" program that is driven by variables that makes 1,000's of different variations of the part. Macro programming also utilizes Logical Functions such as "IF" and "WHILE" to perform functions (machine features) when certain conditions (variables) are true ("EQUAL TO", "LESS THAN", etc.).

We are one of those companies that offers a ton of options, but we also make a high volume of parts. Our proprietary software allows the Sales Dept. to create a file for every action that we sell that sets the variables in the CNC control.

We use macro programming to make countless variations efficiently, giving the customer exactly what they need while keeping the cost down.

View attachment 7856726
View attachment 7856727

I'm getting all moist

 

[sirhrmechanic]

Can I play? This is what I did today.

New ring gear on a flywheel to fix the one some clown shoes tried to weld. Interrupted cut to remove welded teeth and harder-than-woodpecker-lips metal overheated in welding.

Never weld a ring gear.

LeBlonde Gap Bed lathe c 1950’s.

No CNC, but It does have a dro.

Sirhr

New ring gear shrunk in place and ready for Dutchman pins.

That’s a 24” vernier…

Sirhr

 

[Average guy]

Can I play? This is what I did today.

New ring gear on a flywheel to fix the one some clown shoes tried to weld. Interrupted cut to remove welded teeth and harder-than-woodpecker-lips metal overheated in welding.

Never weld a ring gear.

LeBlonde Gap Bed lathe c 1950’s.

No CNC, but It does have a dro.

SirhrView attachment 7871225
View attachment 7871227


View attachment 7871226
New ring gear shrunk in place and ready for Dutchman pins.

That’s a 24” vernier…

Sirhr

Why would you weld that. All of them I’ve ever worked on are an interference fit. Heat the gear to remove and install.

 

[sirhrmechanic]

Why would you weld that. All of them I’ve ever worked on are an interference fit. Heat the gear to remove and install.

Exactly.

But there’s always that guy who thinks they can save a buck or short cut the process by whipping out the stick welder and the angle grinder and globbing some weld on a ring gear set of teeth.

The only thing they accomplished was too harden the tooth roots so much that they started cracking off immediately. And put so much heat in the fly wheel that they are lucky they didn’t warp it and they left a hard spot that was half an inch deep.

The ring gears on these two pre-war flywheels (the sharp eyed will notice there are two flywheels there one I did on Friday one I did today) are integral. Also the bolts holding it in place are taper and ream fit. So the fly wheel doesn’t just drop right off.

So people decide that they have a better idea than doing the job right and simply end up making it far more expensive in the long run. The unwelded fly wheel cut and had a new ring gear on it in about six hours. The other one with the weld took about 10.

But plenty of folks think they can weld a ring gear. It’s what makes restoration machining so much fun.

Sirhr

 

[LeftyJason]

Exactly.

But there’s always that guy who thinks they can save a buck or short cut the process by whipping out the stick welder and the angle grinder and globbing some weld on a ring gear set of teeth.

The only thing they accomplished was too harden the tooth roots so much that they started cracking off immediately. And put so much heat in the fly wheel that they are lucky they didn’t warp it and they left a hard spot that was half an inch deep.

The ring gears on these two pre-war flywheels (the sharp eyed will notice there are two flywheels there one I did on Friday one I did today) are integral. Also the bolts holding it in place are taper and rim fit. So the fly wheel doesn’t just drop right off.

So people decide that they have a better idea than doing the job right and simply end up making it far more expensive in the long run. The unwelded fly wheel cut and had a new ring gear on it in about six hours. The other one with the weld took about 10.

But plenty of folks think they can welder ring gear. It’s what makes restoration machining so much fun.

Sirhr

I started reading that post up above and thought didn't I already watch you do that? Cool stuff.

 

[308pirate]

Exactly.

But there’s always that guy who thinks they can save a buck or short cut the process by whipping out the stick welder and the angle grinder and globbing some weld on a ring gear set of teeth.

The only thing they accomplished was too harden the tooth roots so much that they started cracking off immediately. And put so much heat in the fly wheel that they are lucky they didn’t warp it and they left a hard spot that was half an inch deep.

The ring gears on these two pre-war flywheels (the sharp eyed will notice there are two flywheels there one I did on Friday one I did today) are integral. Also the bolts holding it in place are taper and ream fit. So the fly wheel doesn’t just drop right off.

So people decide that they have a better idea than doing the job right and simply end up making it far more expensive in the long run. The unwelded fly wheel cut and had a new ring gear on it in about six hours. The other one with the weld took about 10.

But plenty of folks think they can weld a ring gear. It’s what makes restoration machining so much fun.

Sirhr

We have a guy here who thinks he can fix anything with a welder. Just ask him. He also likes airguns.

 

[Mech Eng]

Is that a flat plate? Because… wow!

Sirhr

Yup it is a surface plate we use for measuring a part for a particle accelerator.

 

[The D]

I'm getting all moist

Put it away…

 

[Davess]

Yup it is a surface plate we use for measuring a part for a particle accelerator.

Are you where the forest fires are?

 

[Mech Eng]

Are you where the forest fires are?

No I live in the midwest so no forest fires here that I know of.

 

[Davess]

No I live in the midwest so no forest fires here that I know of.

Thought you might be in NM

 

[Satterlee]

I'm guessing the sinker EDM is set up to burn the helical closing cams in the receiver?

 

[iceng]

We have a guy here who thinks he can fix anything with a welder. Just ask him. He also likes airguns.

Hahaha i think i know that guy. Asshole.

 

[Davess]

Hahaha i think i know that guy. Asshole.

That's like literally every welder out there!

 

[Mech Eng]

Thought you might be in NM

No I live in the lake Michigan area. I just found this picture from my machinist days tolerances on these parts were 0.0005" we didn't have any CNC's so it was all manual machines

 

[Defiance Machine]

Precision is everything.

The receiver is the heart of the rifle, and the hole going through the center, the feature that all others are based upon. The bore of the receiver is critical, as the diameter and straightness affect accuracy. Just as important is that the barrel threads in the receiver are concentric, and the receiver face and locking lug abutments are perpendicular to the bore. For this reason, we machine all these features in one operation.
When done properly, a barrel that gets screwed into the receiver will align perfectly with the two bores, concentric to each other, and under no stress from a receiver face that is out of square. This is the start of a superbly accurate rifle.

Drilling a precise hole through nearly 10” of hardened steel is not a simple task. We start by purchasing high precision lathes and having them equipped with high pressure oil coolant pumps. A common twist drill does not generally drill a hole that is straight, round, or a precise diameter. Gun drills do. After we drill and bore a pilot, the gun drill creates a precise hole straight through the receiver blank. We could leave well enough alone, but because the tool will wear, part number one and part twenty would be different.

Therefore, we gun drill slightly undersized and hone the receiver blanks to the finish diameter. The honing machine spins a mandrel with abrasive stones in the bore while moving it forward and back. The result is a smooth, round hole with a consistent diameter that is measured to .0001” resolution. That’s 1/30th the thickness of a human hair for the non-machinist types out there.

 

[Defiance Machine]

Legacy Bolt Process​

The bolts found on our Deviant and Rebel actions are manufactured differently than the bolts in the rest of our product line as they are machined with a full-length handle.

Manufacturing a one-piece bolt of this style is a bit of an adventure.

We start with a rectangular block of hardened steel from which we will get two bolts.

There is a deep hole through the center for the firing pin that needs to be concentric to the outside diameter. Drilling deep holes straight is always a little challenging, not to mention in pre-hardened 4340.

The handle is also a lathe-turned feature, but it is not perpendicular or centered to the body.

There are always multiple ways a part can be made, and at the end of the day we come up with a process that efficiently creates the best product possible. This part has a significant number of operations including a 3-axis mill, waterjet, 5-axis mill, mill-turn center, another 5-axis mill, and a 4-axis mill.

There are certainly faster methods to make a bolt for a rifle but when the product demands precision, elegance, and bomb-proof reliability, your options are much fewer.

 

[ShtrRdy]

I'm lovin' this series.

 

[Zatchmo]

It’s kinda like soft core porn though. Just enough to make you want more detail.

But seriously, please keep this up as long as you can. It’s really great to see.

 

[Defiance Machine]

Defiance anTi X Bolt unloaded with Robotic (Pneumatic) Grabber​

​

This pneumatic gripper is now being utilized to run parts in a fully automated process.

These bolts are machined from a 6’ bar, about 6” at a time.

The CNC program begins with a minimal amount of bar stock protruding from the main spindle.

After the front end of the bolt is machined, the sub spindle advances and grabs the bolt.

Next, the main spindle unclamps, allowing the sub spindle to pull the bar out farther before clamping again and machining the body of the bolt.

We electronically probe the bolt after each “pull,” to ensure that we know exactly where it is “in space,” and so we can hold tight tolerances across key features.

Lastly, the sub spindle chokes up on the bolt leaving only a small amount protruding and the back end of the bolt is machined to completion. We have now machined a complete bolt in just one operation, allowing us to create very precise and consistent parts.

Before the addition of the pneumatic grabber, the machine might sit for a short time while the operator finishes up some other task (like loading or unloading another machine). This may just be a minute or it may be 10 minutes. Minutes add up and we need to be as efficient as possible. With the addition of these pneumatic grabbers, the machine pulls the finished part out of the spindle, drops it onto a conveyor, and starts machining the next part.

Machinists and operators are still running the machines, checking and measuring parts, loading new bars of steel, making adjustments, changing and qualifying the tools, etc. There will be less “lost time” however. And when the crew is heading home for the night, a new bar can be loaded, and parts can be run for hours after we have shut-off the lights and gone home to bed.

At Defiance, we are constantly seeking ways to be more efficient, so we can better serve our customers.

 

[DocRDS]

Maybe the wrong thead, but why does everyone machine from bar stock? Seems there might be a way to cast a smaller piece/heat treat and mill down (maybe it was the afore mentioned stress)--especially given the 90% material reduction. I'm sure there is a reason, but would love to understand the insight.

 

[Hobo Hilton]

Maybe the wrong thead, but why does everyone machine from bar stock? Seems there might be a way to cast a smaller piece/heat treat and mill down (maybe it was the afore mentioned stress)--especially given the 90% material reduction. I'm sure there is a reason, but would love to understand the insight.

Some still hammer forge.

LRB Arms M14SA & M25 Receivers

M14SA & M25 Receivers

www.lrbarms.com

 

[kyzim311]

Maybe the wrong thead, but why does everyone machine from bar stock? Seems there might be a way to cast a smaller piece/heat treat and mill down (maybe it was the afore mentioned stress)--especially given the 90% material reduction. I'm sure there is a reason, but would love to understand the insight.

Castings always have defects, and the shape of the item along with controlling the process determines where they are and how many you have. Bar stock is made through extrusion and has less defects, so you end up with a better part. Powder metal would be a good in between process to reduce material removal, but quantities need to be high for this to make sense economically.

 

[Tokay444]

Defiance anTi X Bolt unloaded with Robotic (Pneumatic) Grabber​

​

This pneumatic gripper is now being utilized to run parts in a fully automated process.

These bolts are machined from a 6’ bar, about 6” at a time.

The CNC program begins with a minimal amount of bar stock protruding from the main spindle.

After the front end of the bolt is machined, the sub spindle advances and grabs the bolt.

Next, the main spindle unclamps, allowing the sub spindle to pull the bar out farther before clamping again and machining the body of the bolt.

We electronically probe the bolt after each “pull,” to ensure that we know exactly where it is “in space,” and so we can hold tight tolerances across key features.

Lastly, the sub spindle chokes up on the bolt leaving only a small amount protruding and the back end of the bolt is machined to completion. We have now machined a complete bolt in just one operation, allowing us to create very precise and consistent parts.

Before the addition of the pneumatic grabber, the machine might sit for a short time while the operator finishes up some other task (like loading or unloading another machine). This may just be a minute or it may be 10 minutes. Minutes add up and we need to be as efficient as possible. With the addition of these pneumatic grabbers, the machine pulls the finished part out of the spindle, drops it onto a conveyor, and starts machining the next part.

Machinists and operators are still running the machines, checking and measuring parts, loading new bars of steel, making adjustments, changing and qualifying the tools, etc. There will be less “lost time” however. And when the crew is heading home for the night, a new bar can be loaded, and parts can be run for hours after we have shut-off the lights and gone home to bed.

At Defiance, we are constantly seeking ways to be more efficient, so we can better serve our customers.

Shunk gripper?

 

[LeftyJason]

Maybe the wrong thead, but why does everyone machine from bar stock? Seems there might be a way to cast a smaller piece/heat treat and mill down (maybe it was the afore mentioned stress)--especially given the 90% material reduction. I'm sure there is a reason, but would love to understand the insight.

Building on what @kyzim311 said. Bar stock can come with certificates as to the state of the material in regard to voids and other things. At my work we cast lots of parts for aerospace and alot of them are xrayed. There are certain voids allowed. Barstock parts are generally dye penetration inspected. Another reason is that it can be easier to program and especially hold bar stock vs castings or forgings. Bar stock is consistent size. Castings and forgings vary. If you have the right inserts roughing can go quite fast. You also won't have a hard surface that can be on the surface of forgings. Getting consistency of homogeneity of material in a casting can be hard.

Biggest benefit is bar feeders. Different brand below but concept is the same across all brands.


To load a part that is cast or forged they need to run having the operator load or integrate a robot.

That's a lot harder and much more expensive. Also whenever they use a robot it is generally always loading billets not castings or forgings. Having machined turbine rotor castings at work getting things to true up can be a pain in the butt. We do the castings in house and some parts have been around for 30+ years and they still suck. Having somebody else do castings or forgings for you is more expensive and another step that you aren't in control of.

Also running from bar stock the sales people can claim they are machining parts from billet.

 

[DocRDS]

Much appreciated on the info responses. I have just enough metallurgy knowledge to be a retard.

 

[LeftyJason]

Much appreciated on the info responses. I have just enough metallurgy knowledge to be a retard.

That is still better than most.

 

[The D]

Much appreciated on the info responses. I have just enough metallurgy knowledge to be a retard.

Juuust enough know-how to be a danger to yourself and everyone around you. Welcome to the club

 

[Mike at Defiance]

Maybe the wrong thead, but why does everyone machine from bar stock? Seems there might be a way to cast a smaller piece/heat treat and mill down (maybe it was the afore mentioned stress)--especially given the 90% material reduction. I'm sure there is a reason, but would love to understand the insight.

That's a good question. Certainly, there are ways to make parts with less cost. Castings, MIM, and 3D printing, etc., are all processes that reduce waste and machine time. These savings all come at a cost, however. Locating (in all 5 axes of a CNC machine) a cast part that is inconsistent in dimensions and not straight is more trouble than it's worth, not to mention the voids. MIM and 3D printing cannot replicate the precision or surface finishes that we have with our CNC machines. The above mentioned processes have limited material choices. Our material selection is well thought out to give the customer the best product, not to give us the highest profit. Also, most of these processes would limit options by requiring a mold or tooling. We can make any length, diameter, or style of bolt off the same bar with little or no set up change. Lastly, we have found the best way to manage inventory and quality is to machine everything in house, from pre-hardened bar stock.

 

[DocRDS]

@Mike at Defiance --thanks for the extra details. In all of these manufacturing processes all those little details matter--I know from my work in the Silicon Industry that everyone is going to replace Silicon and yet 30 years later, we're still at it due to the technology invested and the highly evolved product. I expect there is very little difference for receivers and the fact that the industry can put out those tolerances still blows my mind with the tools we have.

I just see all that good steel milled away and cry out like Gollum!! THE PRECIOUS!!!

 

[LeftyJason]

@Mike at Defiance --thanks for the extra details. In all of these manufacturing processes all those little details matter--I know from my work in the Silicon Industry that everyone is going to replace Silicon and yet 30 years later, we're still at it due to the technology invested and the highly evolved product. I expect there is very little difference for receivers and the fact that the industry can put out those tolerances still blows my mind with the tools we have.

I just see all that good steel milled away and cry out like Gollum!! THE PRECIOUS!!!

It gets recycled. At work they start with 300lb rounds of aluminum and they end at 30lb structures for jet engines. No other way to do it.