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300 PRC update

I've quit shooting the 300 PRC till my smith gets a reamer to correct the undersizing issue. Third firing on my RL26 75 grain, ADG brass load makes for *very* firm bolt lift.

Good read here...
PRC Die Problem

What bullets are you using to get to 75 gr of RL 26? I only get to 74ish with 230s and my undersized chamber.
 
Hornady brass new measures:
.530 dia at base
.513 dia at shoulder

Hornady fired brass measures:
.530 dia at base
.515 dia at shoulder

Headspace on the fired brass is .003 longer on most, a couple almost .0035 longer.
 
Hornady brass new measures:
.530 dia at base
.513 dia at shoulder

Hornady fired brass measures:
.530 dia at base
.515 dia at shoulder

Headspace on the fired brass is .003 longer on most, a couple almost .0035 longer.

Your chamber is a bit small (~.002") which is causing higher pressures than normal. Mine comes in at .003" under.

As @DellaDog mentioned, there are some small reamers out there.
 
Rocketmandb,
I was suspect from the first couple shots if it was my chambering job. Guess I should have a talk with my barrelmaker.
 
If I am getting high pressure signs with my handloads using Hornady brass, will a higher quality, more robust brass like Lapua or ADG allow me to use that same load without the pressure signs as seen using the Hornady brass?
For example, using 76.0 grains of Retumbo or H1000 I start to get a sticky bolt. Not any pressure signs on the primer except a little bit of primer flattening with the 76.0 grains of Retumbo. Bullet is a Berger 220 Hybrid.
I did notice my Lapua brass started to develop ejector marks when the primers were much flatter than with Hornady brass. I think the internal volume is smaller though - you might be able to get better velocity on not quite as much charge.

I also saw a decent decrease in SD/ES with the Lapua brass.
 
I just read through the thread on LRH about PRC die problems. Anyone experiencing a problem with their die not sizing enough at the case web area? How many loads are you typically getting on a Lapua brass? What dies would you recommend? What’s Hornady new dimension die mean?
 
I just read through the thread on LRH about PRC die problems. Anyone experiencing a problem with their die not sizing enough at the case web area? How many loads are you typically getting on a Lapua brass? What dies would you recommend? What’s Hornady new dimension die mean?
There is a whole thread on it here. (this thread.)
 
I have Redding dies so I use the Redding version, but yeah, a VLD stem is highly recommended.
I
Those who load the A-Tip do you use Hornady’s special seating stem? Item 397140

Those who load the A-Tip do you use Hornady’s special seating stem? Item 397140
I use the VLD stem from LE Wilson on my inline seater. It works much better than their standard stem. The standard stem would leave lines on the ogive sometimes if seating pressure was on the higher side. I havent had it happen since using their vld stem. I would recommend using one.

Loading 230g atips
 
I searched the thread but didn't see this so, if I missed it, please forgive me.

Does anyone have data for N570 or N565 with the 250 a-tips? Vihtavuori has 565, 568 and 570 for the 225's but that's as heavy as their data goes.
 
I searched the thread but didn't see this so, if I missed it, please forgive me.

Does anyone have data for N570 or N565 with the 250 a-tips? Vihtavuori has 565, 568 and 570 for the 225's but that's as heavy as their data goes.
Call Berger and they will give you data for their 245 EOL.
 
I searched the thread but didn't see this so, if I missed it, please forgive me.

Does anyone have data for N570 or N565 with the 250 a-tips? Vihtavuori has 565, 568 and 570 for the 225's but that's as heavy as their data goes.

I worked up a load for 250s, N570 and Lapua brass (CCI mag primer) - 78.0 gr, 2.900 CBTO (mag length). Started at 75 and worked up - got minor pressure signs at 78.5 and mild ones at 79. Didn’t push it any farther than that - getting 2775 out of a 26” barrel and can.
 
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Thanks! That's faster than I plan on shooting them depending on the recoil since I buy my shotguns in the women's section.
 
Thanks! That's faster than I plan on shooting them depending on the recoil since I buy my shotguns in the women's section.
I shoot a gas Beretta with an oversized gel pad… so I know what you’re thinking! N570 seems to help with recoil - it’s slow burning and more of a push than the snap I’ve gotten out of some magnums.
 
This past Sunday, a friend and I did a local team match. The format was a sniper style match of calling headshots for bonus points or going for the easier-er body shots. This match was at TVP. I've shot here hundreds of time and recently have won 1k and 1 mile bench rest matches and an ELR match. Sunday's match should have been a cake walk of targets ranging from 385 yards to 1140 yards with a bonus shot at 1 mile. Targets were generous since we were shooting IPSECs and 8" rounds for heads. I failed miserably. Why? Hard head and being tired from a long week of work and no sleep?.....PFFT!!! No excuse...but it is what it is. My partner asked me more than once if I had checked my torque on my action screws....and more than once I acted defiant and said yes...at home before the match.

Clue #1. You shoot 40 rounds in the sight in period and still have no clue.
Clue #2. You call a head shot at 385 and center punch it and then transition down a few inches to the body shot and hit 2 feet in front of the target.
Clue #3. You come in 2nd to last place.
Clue #4. Everyone around you is asking WTF is wrong today?
Clue #5. Go to put rifle away for the day and feel a rattle from stock to Barreled action.


Yep...I'm a dumbass and cost my partner a chance at winning...or atleast placing high for the match. SO, I don't like losing. I don't mind it...if someone has a great day and beats me...I'll shake their hand. I don't mind if I know I just don't have it that day, but I did my best and managed a top 10 finish. However, when I have no friggin clue, and my head is no where in the game...I get frustrated. So, today I started a complete tear down of my rifle. I will build it back and check the torque on everything...and I mean EVERYTHING. I will end up replacing most of the bolts, screws, pins and springs with new. I'll also check certain things just before the match starts. This weekend was embarrassing...and I brought it all on myself.

Today so far:

rifleteardown3.png
 
Clue #1. I had that at an ELR match, too. Turns out both the rail and action screws were loose which I discovered 8 stages in!
 
Yep...I'm a dumbass and cost my partner a chance at winning...or atleast placing high for the match. SO, I don't like losing.

Experience often includes pain, but pain is a great teacher. You probably won't make that mistake again. At least the target wasn't shooting back.

To cheer you up, I'll include my latest 300 PRC family add:

568.jpg
 
Dang it. Limit of two one pounders, out of 8. That's just enough to say I love it and have to find more. Two pounds would be gone in, what, 28 rounds? LOL
 
Dang it. Limit of two one pounders, out of 8. That's just enough to say I love it and have to find more. Two pounds would be gone in, what, 28 rounds? LOL
My math is better then my shooting so here you go; 2 pounds = 14,000 gr. so say 76gr per round for your 300PRC = 184 rounds.

Anyway I to would like to hear if anyone has actually used this powder and what they think. I've tried the N565 and found it to be just OK for my rifle.
 
What neck dies are you guys running on Lapua brass? Please provide a range or the best one you found?
 
334 bushing in a Redding neck die.
Is that Lapua Brass...334 bushing? I am measuring the neck .335 out of the box. In my estimate from measuring the brass thickness and inside diameter I estimate .335 = .004-.006 neck tension...tad too much.
 
On my lapua brass I'm using a redding .335 bushing in my FL die. Then .3075 expander mandrel. Getting very consistent seating pressure of 40 psi +/-2 psi on my 21st centry arbor press.
Thanks for the intel. I am probably going to do the same. I have have great luck using a smallish size bushing on 6.5 Creedmoor(.288) then using a mandrel to get .001-.002 neck tension.
 
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Your chamber is a bit small (~.002") which is causing higher pressures than normal. Mine comes in at .003" under.

As @DellaDog mentioned, there are some small reamers out there.
Got my barrel maker to open my chamber up with the correct size reamer. They did get some of the out of spec (undersize) 300 PRC reamers when they originally chambered my barrel.
No more sticky bolt anymore with 76.0 grains of Retumbo or H1000. The barrel is still drilling 5 shots into the same hole at 100 yards. Now I can proceed in increasing my powder charges to see how much more velocity/accuracy I can get out of it.
 
Got my barrel maker to open my chamber up with the correct size reamer. They did get some of the out of spec (undersize) 300 PRC reamers when they originally chambered my barrel.
No more sticky bolt anymore with 76.0 grains of Retumbo or H1000. The barrel is still drilling 5 shots into the same hole at 100 yards. Now I can proceed in increasing my powder charges to see how much more velocity/accuracy I can get out of it.
What size is your brass at the web now? You went from .530" to what?????

My Bergara Premier Approach in 300 PRC shows .532" after firing but I haven't sized or shot anything other than virgin to know if I'm going to run into "issues" in the future.
 
What size is your brass at the web now? You went from .530" to what?????

My Bergara Premier Approach in 300 PRC shows .532" after firing but I haven't sized or shot anything other than virgin to know if I'm going to run into "issues" in the future.
When I measure with my micrometer (versus calipers), the original undersize chamber fired brass was .5295. The brass now is measuring only .001 larger (.5305). This is with Hornady brass and not real hot loads. The main thing is that the bolt is not sticking at all. Before, the bolt was pretty hard to open. I did not ask how much the chamber got opened up.
 
Got my barrel maker to open my chamber up with the correct size reamer. They did get some of the out of spec (undersize) 300 PRC reamers when they originally chambered my barrel.
No more sticky bolt anymore with 76.0 grains of Retumbo or H1000. The barrel is still drilling 5 shots into the same hole at 100 yards. Now I can proceed in increasing my powder charges to see how much more velocity/accuracy I can get out of it.
Same problem I was having with my Christensen, my GS is opening it up right now and hope that fixes the issue. Glad to hear it did for you.
 
Hi,
I was testing my hotest load using 80 gn of N565 with 230 a-tips and I noticed a curious phenomenon, the cases are completely cold and almost 100% clean after shooting (adg virgin brass), a 79 gn load with same bullet an virgin brass comes hot and dirty out of the action.
Could this mean that the 80 gn load is expanding the brass in a way that seals much better and no gases go into the chamber?
There are no bolt stickiness nor ejector marks with this load and primers have reasonably round edges.