First time reloading, oh, and it's 45 RAPTOR

[archangel2003]

OK, I built an AR-10 in the 7.62 NATO, then built one in a wild cat chamber called 45 RAPTOR that is a copy of the 460 S&W Magnum but intended for the AR-10 action.
I got the Lee Classic Turret Press Kit and some accessories.
I also have the dies for 300 BLK and am collecting more of the calibers I own as I can afford them.

I only have yet to purchase a Chronograph to complete what I should need to effectively reload.

Also, there are only a few rifle ranges close enough to get to easily, and those require hundreds to join, so I rarely get to shoot.

The one question I have is, since we all should use a chronograph to check the speed and thereby deduce the pressures and then select the most accurate load.

When I buy 30-06 factory made ammo, how do they determine what is what because if every gun is different and powder lots can vary?

[acoop101]

Reloading companies load to a pressure specification and have the testing equipment to check. They also buy powder by 1000 pound lots. The number they print on there box is the number they get from their test rig. You will be safe if you use established data for the 460 s&w Magnum, check out hodgdons web sight for load data.

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[Scharfschuetze]

When I buy 30-06 factory made ammo, how do they determine what is what because if every gun is different and powder lots can vary?

The larger ammo companies have pizio electric pressure measuring equipment which has generally replaced the older copper crusher method of pressure measurement. Both measurements are still used though and the copper crusher method does not completely tell the story while the strain gauge PE is pretty accurate.

Large companies buy non canister powders and then test them in house for their actual properties. As handloaders, we are lucky that our canister powders are so uniform from lot to lot and decade to decade.

They also use a specially designed universal receiver that uses interchangeable barrels to measure ballistics in a controlled environment (ie. tunnel). The barrels and chambers are all SAAMI spec in dimensions. They just have to accept that not all rifles are the same and load safely for the average. The fear of tight bores or specifications is one reason why US commercial 8mm Mauser and to some extent 9mm Parabellum ammo is loaded to lower pressures than in Europe.

[wiljen]

When I buy 30-06 factory made ammo, how do they determine what is what because if every gun is different and powder lots can vary?

The process of working up a factory load has been pretty well stated above. What hasn't been explained is the part about with every gun being different how do they know what is safe.

The answer is simple. They load to the least common denominator. Thus 7mm Mauser is always loaded as if you were going to put it in a 1890s made lowe rifle. For the 45-70 assume it will be put in a trapdoor. For the 30-06 assume an early model 1903. That is why a lot of factory ammo can be improved upon when handloading. If you dont have the weakest action produced for a cartridge, there is room for improvement in most cases.

Having said that, the 460 is a new round and no guns more than approx 10 years old exist for it. There are no weak actions associated with it so the data is probably pretty much maxed out unless you build something with a cannon breach that can withstand higher than normal pressures. In this case, the design of the AR action may become the limiting factor in that an AR-10 designed for the 7.62x51 at 61,000 PSI max may not function correctly with a load that generates higher gas pressures or more case head thrust.

The 460 does have a larger case head than the 7.62 so it will have more case head thrust at the same pressure level. This is easy to think about if you look at a contender which can be chambered in 222 and 45-70. With the smaller .222 case, pressures of 65,000 PSI are acceptable in that frame, with the larger 45-70 case, pressures above trapdoor level (28000 PSI) will wreck the frame in short order. Pressure has to be combined with case head size to determine how much case head thrust is going to slam into the bolt and how big a buffer and how heavy a spring you will need to offset it.

It is quite possible that with the larger case head of the 460 (.520 vs .473) that a heavier buffer, a heavier spring, and / or an adjustable gas port may all be in order.

[acoop101]

The process of working up a factory load has been pretty well stated above. What hasn't been explained is the part about with every gun being different how do they know what is safe.

The answer is simple. They load to the least common denominator. Thus 7mm Mauser is always loaded as if you were going to put it in a 1890s made lowe rifle. For the 45-70 assume it will be put in a trapdoor. For the 30-06 assume an early model 1903. That is why a lot of factory ammo can be improved upon when handloading. If you dont have the weakest action produced for a cartridge, there is room for improvement in most cases.

Having said that, the 460 is a new round and no guns more than approx 10 years old exist for it. There are no weak actions associated with it so the data is probably pretty much maxed out unless you build something with a cannon breach that can withstand higher than normal pressures. In this case, the design of the AR action may become the limiting factor in that an AR-10 designed for the 7.62x51 at 61,000 PSI max may not function correctly with a load that generates higher gas pressures or more case head thrust.

The 460 does have a larger case head than the 7.62 so it will have more case head thrust at the same pressure level. This is easy to think about if you look at a contender which can be chambered in 222 and 45-70. With the smaller .222 case, pressures of 65,000 PSI are acceptable in that frame, with the larger 45-70 case, pressures above trapdoor level (28000 PSI) will wreck the frame in short order. Pressure has to be combined with case head size to determine how much case head thrust is going to slam into the bolt and how big a buffer and how heavy a spring you will need to offset it.

It is quite possible that with the larger case head of the 460 (.520 vs .473) that a heavier buffer, a heavier spring, and / or an adjustable gas port may all be in order.

But the 460 is a rimmed case, the volume of these two cases are nearly identical,c that said on the 45 raptor web sight it specifically says to use 460 s&w load data.

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[wiljen]

I'm not debating the use of 460 data, I'm suggesting that a design meant for a smaller rimmed 7.62 is going to need some alteration to work properly with a cartridge that produces a larger case head thrust. If the 45 Raptor is rebated to match the 308 in rim diameter, then you can probably use the same buffer and an adjustable gas block since the case capacity of the 460 is a good bit higher than that of the 7.62 and thus the gas port pressure is likely to be proportionally higher.

[Tackleberry41]

Book data is usually little more than a guide. Its rare to use provided data and get the exact same velocity as they show. I was messing with some 308 recently, loaded light for a Spanish mauser. The velocity provided was worthless as all the data came from a 24in barrel, since those are what everybody uses in a 308. Theres not really a formula to come up with the velocity loss for the shorter barrel. Theres some rules of thumb people go by, but actual results will vary widely.

So the 30-06 example you provided, you have to look at the specifics. Barrel length, the case used, primers, testing method, temp and altitude, all has an effect.

But you really do need a chronograph, no idea how I reloaded before having one. Yea you can reload safe ammo without one. But a chrony really really helps. I have been messing with some 460 rowland, and what seemed like a perfectly safe load, was not so according to the chrony. A reduced load, below the min given, still showed higher velocity than a max charge. So seems obvious the pressure is a bit high. I will knock back the charge to get it in line with what the velocity should be. I am running a considerably longer OAL length due to running it in a revolver where length isnt an issue. And one would generally see a velocity drop due to more case capacity, but the brass I am using is creating the issue, cut down 454 vs actual 460 brass, thicker, so less capacity.

[Moleman-]

The bolt thrust should be about the same as the ID of the case head area's are about similar which is what the formulas use. I'd previously made a 44x1.8" on a bolt action for use in lower MI based off of 30-06 brass, and made the ar10 version of it this year. Standard spring, buffer, modified Pmag, 16.5" barrel, carbine length gas port @ 0.078", loads mostly in the 52Kpsi to 56.5Kpsi range using LilGun. The 52Kpsi range loads were more accurate so that's what I'm hunting with. Figured the deer wouldn't notice the missing 50fps.

What are you thinking about for a load?

[Harter66]

Also having recently assembled a 45 Raptor .......
The Raptor is assembled on a 308 case straightened and trimmed to 1.8" .
The cartridge head spaces on the mouth like 45 ACP and uses .451/452 dia bullets like both the 45 and 460.
In a recent data search I found a substantial portion of the 460 data is more like 48,000 psi than the 62,000 maximum loads found in only a handful of loads .

To address the OP OQ . Based on my initial case conversions I would recommend a neck reamer or turning tool as I've found several case brands to be too thick to chamber with even .451 jacketed much less the needed .453 in my rifle . Being a bolt gun in my case I intend to down load it to reach the pistol ballistics in the 17" bbl . Treating it more as a 45-70 class cartridge than a pocket rocket for a 5# revolver.

I have loads in all of my pistols that hit pretty much on the numbers . 75% of my rifles clock over 200fps faster than load data would suggest. 1 in particular with a cast PB bullet exceeds the jacketed maximum velocities almost 3 gr below start loads with a powder " too slow to blow up the rifle". Sometimes a component combination in a particular gun will generate unusually high or low velocity . Grab a copy of the Speer manual and read the article "Why ballisticians get grey" . We work up from start loads of tested data . Sometimes we start even lower because we know that a particular case has less space LC 72 Match vs Remington commercial 308 for example . Or if we change to a mag primer from a standard .

It looks to me like the OP did do some homework before he started , he chose the Raptor over at least 4 other 45 cal AR class cartridges .

According to the math the 45-70 Siamese Mausers should have self destructed with 95, 1895 and 96' load data and shouldn't survive Ruger #1 data and yet they do . I also disagree with the math with cartridges like the 50 Beowulf generating less or equal thrust to a 223 . Surely it would be greater in a 284 Win than a 7-08 , in this line of thinking those and the 7x57 ,280 Rem and 280 AI should all generate the identical bolt and head load loaded to the same pressure levels .

Carry on .

[archangel2003]

When I get the Chronograph, I'll do as the book says and begin with the minimum charge.
So, with the range so far away, I doubt I'll get there often.
How does this sound.
I assume on my first trip to the range, I should load something like 5 rounds of each load up to the maximum and stop shooting when I get to the charge with the desired FPS, then pull the bullets on the remaining overloaded rounds and reload them to the new found charge.
Then on my next trip, start shooting for accuracy like I did before but start reducing the load from my new found maximum to see when I get the best accuracy for this rifle/bullet/powder/primer set up.
Then I'll have my load data for that powder lot and can load to my hearts content to prep for TEOTWAWKI.

[Harter66]

Arch
What I do is start at a minimum charge and depending on the charge window and case capacity break it down into steps typically in 308,*57 or 06 of a half grain steps to find function first . Often the start load and even the 2nd won't be functional . After you have function then you can chase groups on up to maximum loads or platform function or adjustment limits . With the steps you should see groups close and then open up . At that point you have a narrow window of maybe 1 gr . Now you can work in steps of .2 or even .1 for the best load .

[Mica_Hiebert]

Velocity is not how you determine a max load. You need to look at things like case head expansion and primer extrusion or flattening. Every gun can get different velocities from the same load with the same pressures. You do not need a chronograph to develope a max or accurate load all a chronograph does is give you ballistic data for a load to help determine bullet drop or maybe hint at what may be an accurate load due to low shot to shot velocity spreads but I've seen many loads with tight extreme spreads shoot patterns on target and I've seen tight groups from loads with horrible round to round velocities. If you want to guesstimate velocity of one of your loads see if you can find 460 data for the encore rifle.

[dragon813gt]

I don't get out the chronograph until I find an accurate load or am looking to make a specific power factor. Both are for essentially the same reason. I want to make sure the round has enough energy on target for hunting purposes. I really don't need the chronograph because I went many many years w/out one. It's just another tool. Velocity doesn't equate to pressure in a linear fashion so you can't use it for that purpose.

[Tackleberry41]

Guess Im lucky, I need to test a load. I make up a couple, walk outside, test em. Not right, easy enough to make a couple more then test those real quick.

[archangel2003]

I went ahead and got a hand held Lee press so I can load prepped cases at the range.
I started purchasing the other casting materials and even got the magneto-speed chronograph.
I got most of the bullet molds to cover the calibers I have, lead (reputable local scrap yard), pewter (thrift store on the cheap for the tin and antimony) and a sizer for installing the gas checks on the 300 grain .45 cal intended for my Raptor.

My local scrap yard sweetie will even "shoot with a radioactive metal alloy tester" my melted lead and pewter ingots so I know what I have.

I even have that neat lead alloy spread sheet that tells the pressure rating and gives the "Estimated minimum peak pressure required for bullet obturation" and "Projected BHN" hardness.

One thing, my Pewter has up to 6% Copper and I read that Copper effects Lead hardness, (but how much % Copper effects Lead, and how much is that effect?) because the Lead alloy spread sheet only lists Tin, Lead and Antimony and my on line search for the specific effect of Copper on Lead bears no fruit.

Could my Lead have been an alloy intended to be used for Babbitt?

Will that much Copper make my rounds harder enough to matter much, like water quenching while casting does?

Small amounts (2-5%) of Tin (filling out the mold and hardness), Antimony (hardness) and (Arsenic for heat treating after casting) seem to effect the Lead bullet hardness greatly.
Shall I assume the other elements of less than .05% (titanium, Iron and Chromium) are just trace elements and are not large enough quantity to matter?

The thing is the lead hardness and velocity.
I read about the excessive pressure beginning to push flame cutting gases past the bullet causing leading of the barrel and how gas checks are supposed to prevent this.
The 45 Raptor with the 300 grain bullets is expected to get near the 2000 fps range.

With copper gas checks, is the hardness of the lead as much of an issue?