300 PRC update

Awesome. Thanks for the reply’s. Just got my 300 Sherman mag back from the gunsmith and should have my 375 ruger should be in next week. I have hornady brass for both but this looks to be the better option for both. I emailed ADG and they said they have no plan to produce either at this time
 
I find using the reamer quicker and much easier to do. I played around with the K&M, but the shell holder difference caused me problems with wobble. I also played around with the Forster neck turning attachment, but you have to take off a fair amount of brass close to the neck, and I was having a hard time gauging exactly where to stop. I didn't want to end up with a donut on the inside and end up having to ream out anyway.

With the reamer, it's a quick and easy process. You're left with a neck that still has a very small amount of variation, but if you want to take 1/2 a thousandth or so off 50% of the exterior to even everything out, it's straight forward and less apt to cause issues.

As to the 21st Century tool, I've never used it, but it looks like a great unit. I've thought about buying one a few times, but the price always pulls me back. With the shell holder, I'm not sure which one would fit.

It's one of the things I like about the Forster tool: The smaller rim size of the 8x68S doesn't really matter. The .532 collett will shrink down enough to grab hold of the .512" rim (barely), and you can always order a custom collett from Forster if you want (I don't think I need to).

With all that said, if you can make an exterior neck turner work for you, then putting the case through an expander die after initial sizing then doing an exterior neck turn will work well.

I ended up getting one for my 22 creedmoor project and the price stung but the fact it uses angled blades to match the shoulder angle was the selling point for me
 
I just added my two-part video to Youtube on fire forming 8x68S for the 300 PRC. The instructional parts total only about six minutes in total, then I add a minute or so of range footage.

I highly recommend going this route. Here are the key points:

- It doesn't take a ton more time to prep an 8x68S case for the 300 than it does a Hornady 300 PRC case. You have to do one extra sizing, more trimming, and the inside neck turning (reamer).
- I fire these fire forming loads for fun and they're accurate.
- RWS cases come in at about $42 per 20, so they're not cheap. However, they are far more consistent and (I hear) will last a lot longer. I got Norma brass on sale for half that.
- The Forster trimmer and reamer I use during prep will run under $200 with shipping.

Part 1:


Part 2:

Can’t find website. Can you send me link please?
 
Finally got around to shooting the Christensen arms Masa in the ballistics lab at work. Shooting the factory Hornady 225 match. I got 2826, 2813, 2820fps. This is out of a 24" barrel. I'm pretty happy with the velocity as it's faster then what Hornady claims which is 2810. Group was right at 1/4". This was the first group out of the rifle. It has a total of 12 rounds fired.
 
Finally got around to shooting the Christensen arms Masa in the ballistics lab at work. Shooting the factory Hornady 225 match. I got 2826, 2813, 2820fps. This is out of a 24" barrel. I'm pretty happy with the velocity as it's faster then what Hornady claims which is 2810. Group was right at 1/4". This was the first group out of the rifle. It has a total of 12 rounds fired.

It would have been too easy for the factory ammo to work for me. To say I'm disappointed in the results is an understatement. Velocity was right around 2860 average out of a 26" which is what I was expecting but I didn't bother shooting more than 3 rd groups as they were 1" at 100 and the best I could muster at 600 was 5.5"

This was with an early lot of ammo. I know the seating depth was changed slightly by .015 since then but I'm not sure that would made that much of a difference. Going to give the A-TIPS a try and see what happens.
 
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It would have been too easy for the factory ammo to work for me. To say I'm disappointed in the results is an understatement. Velocity was right around 2860 average out of a 26" which is what I was expecting but I didn't bother shooting more than 3rd groups as they were 1" at 100 and the best I could muster at 600 was 5.5"

This was with an early lot of ammo. I know the seating depth was changed slightly by .015 since then but I'm not sure that would made that much of a difference. Going to give the A-TIPS a try and see what happens.
For me this will be a hunting rifle. I want to shoot the 212 ELDX factory ammo and see how it shoots. As of right now with the poor brass choice i'm not in a big hurry to reload for it. If the 212's don't shoot to my likings then I'll start reloading and see what the 212 ELDX will do or try something of the VLD variety a try. It seems factory ammo is easily to come by, local store had all of it I could want in both the 212's and 225's.
 
Just got my 300 Sherman mag back from the gunsmith. Barrel is 26 inches with a 1-9 twist. The picture is a 215 hybrid with the start of the boat tail at the base of the neck to fireform the brass next to a 300wm with the 215 seated .020 off the lands. Quite a difference and I’m excited to try the 230 otms and SMKs
 

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Just got my 300 Sherman mag back from the gunsmith. Barrel is 26 inches with a 1-9 twist. The picture is a 215 hybrid with the start of the boat tail at the base of the neck to fireform the brass next to a 300wm with the 215 seated .020 off the lands. Quite a difference and I’m excited to try the 230 otms and SMKs

How do you like the automated powder measure attached to your FX 120 scale?
 
How do you like the automated powder measure attached to your FX 120 scale?

It’s the best investment I’ve made outside my CPS and giraud trimmer. I’m going to a two day match next weekend and was able to throw powder and seat 400 rounds in 2 1/2 hours two nights ago. The best part is variance in charge weight was within .04 grains for the whole batch.
 
I know everyone has their personal favorites and I’m sold on the impacts but a LA TL3 with the CIP is about the perfect action to start with for one of these builds.
 
This is a picture of a new 300 PRC next to a fire formed 300 Sherman mag. It’s got a decent amount of taper taken out and a 40 degree shoulder
 

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Does anyone know the length of the hornady 250 A tip bullet?

Why they won't put the bullet length in their reloading pages, bullet webpage.....or anywhere...is beyond me. I have plenty of the 230's...but not the 250's...so I can't answer the question....it is frustrating.

I assume you are trying to work up some data in a ballistic calc and it asks for bullet length....but you don't have the bullet yet...so you are like WTF?

Even when I bring up 4DOF and input the 250gr A-TIP...it calculates everything for me...but doesn't tell me the length.
 
Why they won't put the bullet length in their reloading pages, bullet webpage.....or anywhere...is beyond me. I have plenty of the 230's...but not the 250's...so I can't answer the question....it is frustrating.

I assume you are trying to work up some data in a ballistic calc and it asks for bullet length....but you don't have the bullet yet...so you are like WTF?

Even when I bring up 4DOF and input the 250gr A-TIP...it calculates everything for me...but doesn't tell me the length.

The A-Max isn’t on it yet, but there’s a list of most of the bullets out there here:

 
Why they won't put the bullet length in their reloading pages, bullet webpage.....or anywhere...is beyond me. I have plenty of the 230's...but not the 250's...so I can't answer the question....it is frustrating.

I assume you are trying to work up some data in a ballistic calc and it asks for bullet length....but you don't have the bullet yet...so you are like WTF?

Even when I bring up 4DOF and input the 250gr A-TIP...it calculates everything for me...but doesn't tell me the length.

That is exactly what i am wanting it for. I have plenty of room in the MRAD magazine, but to get a better understanding of the potential in AB Analytics... i really wanted the length!
 
Yeah I would call Proof then. Shouldn't be an interference fit on the bullet.
Just a follow up. Proof took really good care of me to help solve the problem. We came to the conclusion that Hornady factory ammo has concentricity issues. About 40 of the 100 rounds I tested had this problem. It seems to be worse on the Precision Hunter ELD-X line than the ELD-Match rounds. Does anybody know if Hornady will take returns on problematic ammo?
 
Just a follow up. Proof took really good care of me to help solve the problem. We came to the conclusion that Hornady factory ammo has concentricity issues. Does anybody know if Hornady will take returns on problematic ammo?

I would be REALLY surprised if Hornady guarantees a maximum runout on factory ammo, but I don't know much and primarily shoot handloads in all my chit.
 
Just a follow up. Proof took really good care of me to help solve the problem. We came to the conclusion that Hornady factory ammo has concentricity issues. About 40 of the 100 rounds I tested had this problem. It seems to be worse on the Precision Hunter ELD-X line than the ELD-Match rounds. Does anybody know if Hornady will take returns on problematic ammo?

How much was it out?
 
I could be wrong, but I've never seen an instance where a bullet hits 2 of 4-6 grooves and not the others at the same time. Especially a new barrel.

Perhaps it's hitting 2 locations in the freebore which are making the marks you see, which is a very different situation-- I could see concentricity causing that, and it's much less of a concern than a bullet jammed .050" into the rifling. In fact, that's kind of the purpose of the relatively tight freebore on the PRC's; that the bullet can't get very misaligned in the bore before firing.
 
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Looks like it's a backorder situation, but

Match 300 PRC for $24.67/box at SWFA

Same $24.67/box price on Precision Hunter
 
Looks like it's a backorder situation, but

Match 300 PRC for $24.67/box at SWFA

Same $24.67/box price on Precision Hunter

That's a crazy deal. Think I paid 44 a box from Midway when they first came out.
 
Looks like it's a backorder situation, but

Match 300 PRC for $24.67/box at SWFA

Same $24.67/box price on Precision Hunter

Looks like the 212 came in stock. Only 5 boxes left. The 225 still on backorder or it came in stock and sold out already.
 
Oh, m'gosh. What a read. I WAS, planing to get a 6.5 creed in a year or so and somehow got a blip about the RPR now chambered in...... So I decided to take a little look and see what is this 300PRC thing. I wish I had not because I think it's easier to get through the first half of a Steven King novel than this monster thread.

You guys are really great compiling all of this experience for guy like me who are not yet into ELR yet. The time and money I have saved by spending 2 days to read this are immeasurable.

So, this Sherman Improved chamber? What are the benefits? I took a look at the first page on his post about it on another forum and it did not really say what the advantages are, it just said there were some. And I don't think I can read another 9 pages of forums for awhile. Please break it down for me.

Other than that, I think I'm squared away. You guys with the 10 to 12 pound hunting rigs. Hows your shoulder? I honestly hate brakes and can handle recoil well within human limitation. Can you run these lighter rigs without obnoxious brakes or are they going to beat you like a step child. I would LIKE to have a hikable rifle that won't kill me at the range but understand that we can't always have what we want. Don't tell me to go six five creedmoor, I already know.

Thanks for the memories.
 
Oh, m'gosh. What a read. I WAS, planing to get a 6.5 creed in a year or so and somehow got a blip about the RPR now chambered in...... So I decided to take a little look and see what is this 300PRC thing. I wish I had not because I think it's easier to get through the first half of a Steven King novel than this monster thread.

You guys are really great compiling all of this experience for guy like me who are not yet into ELR yet. The time and money I have saved by spending 2 days to read this are immeasurable.

So, this Sherman Improved chamber? What are the benefits? I took a look at the first page on his post about it on another forum and it did not really say what the advantages are, it just said there were some. And I don't think I can read another 9 pages of forums for awhile. Please break it down for me.

Other than that, I think I'm squared away. You guys with the 10 to 12 pound hunting rigs. Hows your shoulder? I honestly hate brakes and can handle recoil well within human limitation. Can you run these lighter rigs without obnoxious brakes or are they going to beat you like a step child. I would LIKE to have a hikable rifle that won't kill me at the range but understand that we can't always have what we want. Don't tell me to go six five creedmoor, I already know.

Thanks for the memories.

I think the first question you need to ask is are you going to reload for it. If so I think the Sherman is a no brainer. I’m still breaking in my barrel but I’m expecting an increase of about 100 FPS with a 215 Berger over a 300 PRC. The dies are priced similar to what I expect good whidden dies to cost. You can make it by firing standard 300 PRC ammo/brass thru it and can use standard 300 PRC ammo in a pinch. People have gotten half MOA groups doing this which is about halfway thru this thread. If your not going to reloading none of this really matters and I would just stick with the 300 PRC.

I’ve posted them before but attached are pictures of a 300wm vs a 300prc and a 300prc vs an unsized fireformed 300 Sherman case.
 

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If it's hitting rifling there are 2 options, short throat or long bullet.

Concentricity isn't going to cause it to hit rifling early.
There's another option. With a tight free bore of spec .0005" over nominal bullet diameter, a slightly under size reamer paired with a barrel with a groove diameter that's slightly over size has the potential to not completely clean up the lands. Many time I've seen chambers that have one or more lands that run all the way back to the neck. They may only be several tenths tall but they are still there and tall enough to leave a mark on the bullet.

Got to thinking about this. This is in no way a slam on Proof. Just the facts with tight tolerances. It can and does happen anywhere anytime.
 
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Oh, m'gosh. What a read. I WAS, planing to get a 6.5 creed in a year or so and somehow got a blip about the RPR now chambered in...... So I decided to take a little look and see what is this 300PRC thing. I wish I had not because I think it's easier to get through the first half of a Steven King novel than this monster thread.

You guys are really great compiling all of this experience for guy like me who are not yet into ELR yet. The time and money I have saved by spending 2 days to read this are immeasurable.

So, this Sherman Improved chamber? What are the benefits? I took a look at the first page on his post about it on another forum and it did not really say what the advantages are, it just said there were some. And I don't think I can read another 9 pages of forums for awhile. Please break it down for me.

Other than that, I think I'm squared away. You guys with the 10 to 12 pound hunting rigs. Hows your shoulder? I honestly hate brakes and can handle recoil well within human limitation. Can you run these lighter rigs without obnoxious brakes or are they going to beat you like a step child. I would LIKE to have a hikable rifle that won't kill me at the range but understand that we can't always have what we want. Don't tell me to go six five creedmoor, I already know.

Thanks for the memories.
I built one of the first official 300 PRC's early last year for an Africa trip. 9 lb. rifle I put a brake on it but never hunted with it. Not to bad to shoot without the brake. At least for a few rounds.
Have a brake for the range but take it off for hunting.
 
I think the first question you need to ask is are you going to reload for it. If so I think the Sherman is a no brainer. I’m still breaking in my barrel but I’m expecting an increase of about 100 FPS with a 215 Berger over a 300 PRC. The dies are priced similar to what I expect good whidden dies to cost. You can make it by firing standard 300 PRC ammo/brass thru it and can use standard 300 PRC ammo in a pinch. People have gotten half MOA groups doing this which is about halfway thru this thread. If your not going to reloading none of this really matters and I would just stick with the 300 PRC.

I’ve posted them before but attached are pictures of a 300wm vs a 300prc and a 300prc vs an unsized fireformed 300 Sherman case.

AS for reloading, yea, I think it would be a shame not to learn how to get the most out of it. Thanks for posting the pics again, I seen them though. I have read this entire 28 page gem. What is the cost of those 100 fps? Is it causing a lot more pressure in the chamber and eating up the throat faster? I ask because you are fire forming brass to get your first round of Sherman cases, so that cuts into your barrel life. If I'm off base please let me know. I'm just trying to see figure things out.
 
AS for reloading, yea, I think it would be a shame not to learn how to get the most out of it. Thanks for posting the pics again, I seen them though. I have read this entire 28 page gem. What is the cost of those 100 fps? Is it causing a lot more pressure in the chamber and eating up the throat faster? I ask because you are fire forming brass to get your first round of Sherman cases, so that cuts into your barrel life. If I'm off base please let me know. I'm just trying to see figure things out.
That first round is perfectly acceptable and equal to normal 300PRC loads with velocity and accuracy. Just like a normal AI chamber or a dasher for example.

Higher case capacity from less taper and sharper shoulder equals more powder and higher velocity. Steeper shoulder less neck growth
 
AS for reloading, yea, I think it would be a shame not to learn how to get the most out of it. Thanks for posting the pics again, I seen them though. I have read this entire 28 page gem. What is the cost of those 100 fps? Is it causing a lot more pressure in the chamber and eating up the throat faster? I ask because you are fire forming brass to get your first round of Sherman cases, so that cuts into your barrel life. If I'm off base please let me know. I'm just trying to see figure things out.

B6graham said it perfect. You get 300prc performance for the first firing and then it’s good from there. I expect rich will get brass already formed before to long so no fire forming at all when that happens. I’m only doing 65 cases as it’s a hunting rifle and I expect around 1000 rounds till the barrels shot out so a very small margin will be at the regular performance.
 
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I am originally hoping for 1200 rounds out of the PRC barrel with excellent accuracy. Over a 1/3 of the way and I feel like it's going to go longer. Time will tell.

I will say I did gain 60 fps after about 150 ish rounds down the barrel. Cleans super fast and almost no copper. Impressed with the Proof barrels across the board so far.

Guess I'll keep on what I'm doing and see how it pans out.
 
AS for reloading, yea, I think it would be a shame not to learn how to get the most out of it. Thanks for posting the pics again, I seen them though. I have read this entire 28 page gem. What is the cost of those 100 fps? Is it causing a lot more pressure in the chamber and eating up the throat faster? I ask because you are fire forming brass to get your first round of Sherman cases, so that cuts into your barrel life. If I'm off base please let me know. I'm just trying to see figure things out.

Why not buy a Hydro forming die from Whidden and save your barrel's life