PSA 300 BLK upper, any good?

Grafs has three brands in stock right now, two used and one new. Midsouth has two sizes of used for two bits a case. But you probably have a pile of 223/556 from your other AR adventures I'm guessing.

I was going to say this: FWIW I would use something very low cost like a Lee for the initial sizing after chopping the neck off the 223 just because if you don't heavily deburr before you neck it down you could scratch the die up pretty badly. Use something low cost to do the bulk work, trim and clean them up really nice, then run them through a small base die before loading and after being fired.

Then I found this poking around for the case trimmer I use and found this:

With that I bet you could put the new shoulder on first and cut them much closer to the target length really fast, then run them through a trimmer to finish.

I use a World's Finest Case Trimmer, does high volume work much easier than trying to spin by hand for the final trim step. Not a Giraud but costs a lot less to burn up on bulk work.
 
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Grafs has three brands in stock right now, two used and one new. Midsouth has two sizes of used for two bits a case. But you probably have a pile of 223/556 from your other AR adventures I'm guessing.

I was going to say this: FWIW I would use something very low cost like a Lee for the initial sizing after chopping the neck off the 223 just because if you don't heavily deburr before you neck it down you could scratch the die up pretty badly. Use something low cost to do the bulk work, trim and clean them up really nice, then run them through a small base die before loading and after being fired.

Then I found this poking around for the case trimmer I use and found this:

With that I bet you could put the new shoulder on first and cut them much closer to the target length really fast, then run them through a trimmer to finish.

I use a World's Finest Case Trimmer, does high volume work much easier than trying to spin by hand for the final trim step. Not a Giraud but costs a lot less to burn up on bulk work.
Couldn't I resize the case and then cut it, and you say I should use the small base sizer after every firing I was under the impression this was for first sizing and then use regular FL die
 
You can use small base dies continually, or never use them at all. Depending on the chamber in the barrel it may or may not actually be necessary. I think I have a 223 Rem SB set, but I've never needed one for 300 BLK. I was saying don't use the CB die first because if you cut a case, don't deburr, then jam a piece of brass up in the die you can wreck the die, so don't wreck a more expensive RCBS die when you could sacrifice a cheaper Lee. Then use the SB die on the cut, cleaned up, deburred brass for a final initial sizing.

But that was the old way - honestly I hadn't ever really considered NOT cutting the case first. Then I found that little jig. Resizing first is what I meant by putting the new shoulder on before cutting - resize the 223 case in the 300 BLK die, have two shoulders and the case grows a touch, then cut. I'd never considered not cutting first because I aligned the cut based on the 223 Rem shoulder location, but that little jig makes it look much easier to cut a resized case more accurately than I could with an angle grinder and a vice (it was tough times in the way back 😂 ). So resizing first then cutting is probably the better process, yes, especially if you have that little jig and a chop saw or a band saw to make a much cleaner and better cut.
 
You can use small base dies continually, or never use them at all. Depending on the chamber in the barrel it may or may not actually be necessary. I think I have a 223 Rem SB set, but I've never needed one for 300 BLK. I was saying don't use the CB die first because if you cut a case, don't deburr, then jam a piece of brass up in the die you can wreck the die, so don't wreck a more expensive RCBS die when you could sacrifice a cheaper Lee. Then use the SB die on the cut, cleaned up, deburred brass for a final initial sizing.

But that was the old way - honestly I hadn't ever really considered NOT cutting the case first. Then I found that little jig. Resizing first is what I meant by putting the new shoulder on before cutting - resize the 223 case in the 300 BLK die, have two shoulders and the case grows a touch, then cut. I'd never considered not cutting first because I aligned the cut based on the 223 Rem shoulder location, but that little jig makes it look much easier to cut a resized case more accurately than I could with an angle grinder and a vice (it was tough times in the way back 😂 ). So resizing first then cutting is probably the better process, yes, especially if you have that little jig and a chop saw or a band saw to make a much cleaner and better cut.
 
Just thought of something, doesn't the SB die just size down the body or will it make the neck smaller too, I also have a SB die for 223 but I only used it a few times, was told I need it for my AR-15 many years ago at gun shop, after I got a stuck case I figured I'd try my regular 223 die and have never had a problem so been using it ever since. But isn't the problem with regular 300blk die the spring back in the neck when reforming 223 brass
 
SB die is cut slightly smaller and is longer at the web, no differences from a normal FL in the shoulder/neck I don't think. I've never used a small base 300 BLK, everything has cycled fine.
 
SB die is cut slightly smaller and is longer at the web, no differences from a normal FL in the shoulder/neck I don't think. I've never used a small base 300 BLK, everything has cycled fine.
You have used normal FL die to resize 223 brass to 300blk? If SB die doesn't do anything to neck then I don't see why it would be necessary unless of course your chamber is tight but don't see this happening on a PSA or AP
 
Oh BTW, will your ar shoot better with a tight lower and upper or doesn't it make a difference, tightened mine up, been 0 degrees here and lots of snow so been riding sled instead of shooting but got some good bullets ready to go, we'll see.
 
You have used normal FL die to resize 223 brass to 300blk? If SB die doesn't do anything to neck then I don't see why it would be necessary unless of course your chamber is tight but don't see this happening on a PSA or AP
A small base die is just that - they size smaller further down towards the base of the case, and to slightly smaller overall dimensions. They're used for actions that don't have the benefit of leverage to close the chamber - ARs, semi-autos, pumps. The forward assist is the backup for failure to close because you can smack it and accomplish the same effect as a lever/bolt.

In a bolt action as the bolt closes and the lugs lock there is a compound camming action where the bolt moves forward very slightly to lock with the bolt acting as a lever to gain mechanical advantage. If the case web is slightly oversize it's not ideal, but also not as big a problem because the bolt can lever it into the chamber easier.

You're worried that everyone complains Lee isn't a "forming" die I'm guessing? In the original method of cut-size-trim there was a 4th step of resize down with a second, potentially better die. I said use a Lee die because you could get one for fifteen bucks and size down in two steps whereas a carbide Dillon was a hundred bucks plus.

Forming Process - My Old Poor Boy Method before I gave up and started buying 300 BLK brass because this sucked
  1. Cut down range brass with an angle grinder
  2. Knock the burr off with a bench grinder
  3. Form through a die <--- Buy a crappy Lee for here
  4. Trim to length, chamfer, deburr - all by hand
  5. Resize again in (Forster?) 300 Whisper die <--- Use any die here, SB or otherwise
  6. Shoot, resize with the 300 Whisper die
300 BLK old.jpg



But after seeing that jig and things changing for the better in the last ten years I would now probably do something like:
  1. Resize 223 case with RCBS small base 300 BLK die and put the second shoulder on the case (SB because the case won't grow longer on future sizings if you squeeze it down tight before cutting it)
  2. Cut to very close to trim length with the jig and a little chop saw
  3. Trim in the LCG-WFT on a drill
  4. Probably will chamber in your AR
  5. Resize with whatever die works going forward. Probably a regular FL die because I've never needed a SB die before.
300 blk new.jpg



It seemed like after Dillon came out with the trim die it was popular to use a 223 sizing die as the decapper up front, then use the power trimmer, but I didn't have Dillon money to actually try that out back then.

Oh BTW, will your ar shoot better with a tight lower and upper or doesn't it make a difference, tightened mine up, been 0 degrees here and lots of snow so been riding sled instead of shooting but got some good bullets ready to go, we'll see.
I've never tried to tighten up an AR. I've also never shot a high end service rifle competition type rifle that might be accurate enough to benefit from it. It's my understanding that the Accu-Wedge is snake oil, but I've never used one.
 
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A small base die is just that - they size smaller further down towards the base of the case, and to slightly smaller overall dimensions. They're used for actions that don't have the benefit of leverage to close the chamber - ARs, semi-autos, pumps. The forward assist is the backup for failure to close because you can smack it and accomplish the same effect as a lever/bolt.

In a bolt action as the bolt closes and the lugs lock there is a compound camming action where the bolt moves forward very slightly to lock with the bolt acting as a lever to gain mechanical advantage. If the case web is slightly oversize it's not ideal, but also not as big a problem because the bolt can lever it into the chamber easier.

You're worried that everyone complains Lee isn't a "forming" die I'm guessing? In the original method of cut-size-trim there was a 4th step of resize down with a second, potentially better die. I said use a Lee die because you could get one for fifteen bucks and size down in two steps whereas a carbide Dillon was a hundred bucks plus.

Forming Process - My Old Poor Boy Method before I gave up and started buying 300 BLK brass because this sucked
  1. Cut down range brass with an angle grinder
  2. Knock the burr off with a bench grinder
  3. Form through a die <--- Buy a crappy Lee for here
  4. Trim to length, chamfer, deburr - all by hand
  5. Resize again in (Forster?) 300 Whisper die <--- Use any die here, SB or otherwise
  6. Shoot, resize with the 300 Whisper die
View attachment 334602


But after seeing that jig and things changing for the better in the last ten years I would now probably do something like:
  1. Resize 223 case with RCBS small base 300 BLK die and put the second shoulder on the case (SB because the case won't grow longer on future sizings if you squeeze it down tight before cutting it)
  2. Cut to very close to trim length with the jig and a little chop saw
  3. Trim in the LCG-WFT on a drill
  4. Probably will chamber in your AR
  5. Resize with whatever die works going forward. Probably a regular FL die because I've never needed a SB die before.
View attachment 334604


It seemed like after Dillon came out with the trim die it was popular to use a 223 sizing die as the decapper up front, then use the power trimmer, but I didn't have Dillon money to actually try that out back then.


I've never tried to tighten up an AR. I've also never shot a high end service rifle competition type rifle that might be accurate enough to benefit from it. It's my understanding that the Accu-Wedge is snake oil, but I've never used one.
I wonder what the pros do with the slop or maybe their guns don't have any to begin with, one of the things I read with the lee die is to size it first with 223 FL die before going to BLK die, don't get how that would make a difference but I guess it all depends on the brass
 
A small base die is just that - they size smaller further down towards the base of the case, and to slightly smaller overall dimensions. They're used for actions that don't have the benefit of leverage to close the chamber - ARs, semi-autos, pumps. The forward assist is the backup for failure to close because you can smack it and accomplish the same effect as a lever/bolt.

In a bolt action as the bolt closes and the lugs lock there is a compound camming action where the bolt moves forward very slightly to lock with the bolt acting as a lever to gain mechanical advantage. If the case web is slightly oversize it's not ideal, but also not as big a problem because the bolt can lever it into the chamber easier.

You're worried that everyone complains Lee isn't a "forming" die I'm guessing? In the original method of cut-size-trim there was a 4th step of resize down with a second, potentially better die. I said use a Lee die because you could get one for fifteen bucks and size down in two steps whereas a carbide Dillon was a hundred bucks plus.

Forming Process - My Old Poor Boy Method before I gave up and started buying 300 BLK brass because this sucked
  1. Cut down range brass with an angle grinder
  2. Knock the burr off with a bench grinder
  3. Form through a die <--- Buy a crappy Lee for here
  4. Trim to length, chamfer, deburr - all by hand
  5. Resize again in (Forster?) 300 Whisper die <--- Use any die here, SB or otherwise
  6. Shoot, resize with the 300 Whisper die
View attachment 334602


But after seeing that jig and things changing for the better in the last ten years I would now probably do something like:
  1. Resize 223 case with RCBS small base 300 BLK die and put the second shoulder on the case (SB because the case won't grow longer on future sizings if you squeeze it down tight before cutting it)
  2. Cut to very close to trim length with the jig and a little chop saw
  3. Trim in the LCG-WFT on a drill
  4. Probably will chamber in your AR
  5. Resize with whatever die works going forward. Probably a regular FL die because I've never needed a SB die before.
View attachment 334604


It seemed like after Dillon came out with the trim die it was popular to use a 223 sizing die as the decapper up front, then use the power trimmer, but I didn't have Dillon money to actually try that out back then.


I've never tried to tighten up an AR. I've also never shot a high end service rifle competition type rifle that might be accurate enough to benefit from it. It's my understanding that the Accu-Wedge is snake oil, but I've never used one.
I don't really care what die does the job but was hoping to buy one die set, only brass that is reasonable is once fired from what I can see
 
So either load it hot with something like a 101gn Hammer BlackOut and shoot it like a 30-30, or load it slow with an expanding mono like the Makers and shoot it like a bow. Put a two-layer Ballistix turret label on your scope and switch back and forth.

This right here is truth. All the summary one needs to know.

My son has taken deer and hogs w/ subsonic monos, as well as with supersonic 110-grain NBT. Just make sure you know your distances and drops with subsonic—past 100 yards that projectile is falling like a rock. As mentioned, it maintains energy quite well, but your vertical hold calculations must be spot on.
 
I shot a 7.5" 7 twist that was very accurate. I was pinging a 8" steel target at 150 yrds. Seems to be well made.
 
Thinking of getting a PSA 300 BLK for deer hunting, shooting past 300yds would be not so likely in my area, I was thinking of just getting the upper and around 10 inch barrel, would make it nice and light and easy to carry since I have a lot of brush here, also would only be around 300.00 cause I can put the upper on lowers I already have, does have to be a match gun but don't want junk either, what do you think?
I built a psa 300 blk pistol with 7.5 barrel and it is very accurate out to 100. 150 yds. Best load for me has been 110 gr vmax on top of 19.5 grains of H 110
 
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