-
Having trouble using the site?
Contact support
300 PRC update
- Thread starter DAVETOOLEY
- Start date
Just starting load development on mine. IBI 26" Barrel, AW2 reamer,Lapua brass, N568 and Berger 220 LRHT.
Loaded up 40 rounds from 80-83g of n568. 2825-2950fps range. Knowing my barrel will speed up when its breaks in around 150-200 rounds what velocity should my end goal be with 220s? No pressure signs on lapua brass at 2950 at 83 grains. What advantage does 3000 give me vs 2900 except .1 mil elevation at a mile?
Loaded up 40 rounds from 80-83g of n568. 2825-2950fps range. Knowing my barrel will speed up when its breaks in around 150-200 rounds what velocity should my end goal be with 220s? No pressure signs on lapua brass at 2950 at 83 grains. What advantage does 3000 give me vs 2900 except .1 mil elevation at a mile?
If you’re shooting LR, your goal should be accuracy w low ES/SD over max velocity. I personally work up multiple loads and test at distance before finalizing a load.
I did this. But when i had the 300PRC bbl made, I had it custom chambered to 3.850' for the specific round I wanted to load with a max charge of a few powders I wanted to use, while taking jump and erosion into account. please note I single feed for ELR and do not hunt(yet). Hope this helps.
I went with a chassis and 3.850” mags. If I built a custom it would probably be a single feed with 250’s or 245’s and the biggest case I could source to send them. The 2 choices are simple off the shelf and God hates a half ass effort.
You should be able to hit the lands with everything but the 245 and 250 gr bullets. At least that's how it played out with my chassis and 3.85" mags (3.74" internal).
I'm wondering if any one has used H50bmg powder? I’m wanting to use it to fire form to 30 Sherman Mag so I don’t burn up any valuable powders.
I ended up trying 24N41 behind 220gr ELD-X and it gave me 2800fps out of 32" tube so it's not ideal but case is fully formed, definitely on the lighter side for pressure. 82gr slightly compressed load with a hard jam on the bullets.
Last edited:
300 PRC Ammo For Sale | SGAmmo.com
SGAmmo bulk ammo for sale. Largest selection online for in stock cheap ammunition!
I’m about to pull the trigger on a new MPA Matrix Pro build, primarily for ELR, but it will see the occasional “sniper style” match. With this in mind, I keep flip flopping on barrel length, twist, and contour. Currently looking at 27-30” and a 1:9 or 1:8 (leaning toward 28”/1:9), with the MPA Match or MTU contour.
I have a bunch of factory Hornady 212eldx and 225eldm ammo I picked up a while back but have also been acquiring 230 and 250 A tips as I find them locally and will likely look for some 220/245 LRHT for future load development. RL26 is my powder choice as I can find it in Alaska with N565/568/H1000 and factory loads as a backup.
Having said all that, anyone care to help steer me toward a barrel length and twist that would best fit my needs/situation?
I have a bunch of factory Hornady 212eldx and 225eldm ammo I picked up a while back but have also been acquiring 230 and 250 A tips as I find them locally and will likely look for some 220/245 LRHT for future load development. RL26 is my powder choice as I can find it in Alaska with N565/568/H1000 and factory loads as a backup.
Having said all that, anyone care to help steer me toward a barrel length and twist that would best fit my needs/situation?
Last edited:
8.5 twist for 250 A-tips. Could go faster if you are wanting to shoot some of the heavy solids. I’d go for the long barrel for the velocity
I just found out about this twist rate calculator by Berger. It might be helpful when doing your research. You can lookup any Berger bullet or just enter the details for non-Berger bullets
bergerbullets.com
Twist Rate Stability Calculator
Our newly updated Twist Rate Stability Calculator not only tells you what your SG is, but it also lets you know if you are reaching your optimized BC.
bergerbullets.com
Thanks. I had seen that calculator but have been reading through forms and articles where more experienced shooters than me go in depth about over-spinning 30cal bullets, especially lighter ones and how many of those issues aren’t usually seen until after the barrel is well broken in. 1:9 seems safer in that regard, especially with a longer barrel which keeps velocity a little higher. I think both will work but just trying to gauge from those who have experience here. I’m probably over thinking it to be honestI just found out about this twist rate calculator by Berger. It might be helpful when doing your research. You can lookup any Berger bullet or just enter the details for non-Berger bullets
Twist Rate Stability Calculator
Our newly updated Twist Rate Stability Calculator not only tells you what your SG is, but it also lets you know if you are reaching your optimized BC.
I shoot the berger 220 in a 1-8 twist 30 inch barrels. From a 30 nosler and haven't Had any issues. I've shot 230 a-tip 250 a-tip as well. Have 500 rds on one barrel the other one has prolly 700 and then my newer one is 400. Haven't shot anything lighter than 220 berger. That being said I have 2 other barrels waiting to be chambered one is another 1-8 and the other 1-9. I like the extra spin for long range I shoot to 2k
Over spinning a bullet is only an issue if bullets start to separate. Faster spinning bullets stay stable into trans/subsonic better.
I haven't had any issues with a 1:8.5 so. about 180 rounds in.
so... to be clear, i am a LESSER experienced ELR shooter (actually pretty new to the game) but I have been working with some folks who are HIGHLY experience ELR guys. One of whom (Dave Tooley) is building my Bartlein 30" 1:9.25 - 1:9 gain-twist to a Defiance Machine RUKUS LA. Another well known name in the ELR world highly recommended 1:8.25 - 1:8. Both are leaders in the field but in the end, I am following Dave's advice.
In my research, one of the narratives pointed out to me was that in an ideal world, the faster twist is better for heavier bullets but the issue that many dont consider is that the faster twist accentuates any defects found in the bullet itself potentially resulting in a reduction in accuracy. The slower twist is less prone to these issues. The calculator shows that i am getting the max value out of that same BC at both twist rates.
For me and based on all the information available, i concur with Daves recommendation.
In my research, one of the narratives pointed out to me was that in an ideal world, the faster twist is better for heavier bullets but the issue that many dont consider is that the faster twist accentuates any defects found in the bullet itself potentially resulting in a reduction in accuracy. The slower twist is less prone to these issues. The calculator shows that i am getting the max value out of that same BC at both twist rates.
For me and based on all the information available, i concur with Daves recommendation.
Right now they are saying 18-20 weeks for the Matrix Pros. The Matrix/BA PMRs are 8-12 weeks depending on the build
This is a really solid assessment and advice. Kinda confirms what I was reading as well with a 1:9. I’ll probably do a 29 (or 29.5 if they let me). Thanks!
That sounds like the same discussion had when deciding between 9T and 12-14T 22LR barrels.
Dropped another video on RUMBLE - where you can still load Std. Capacity mags in an AR...
Anyway.. the rain started coming in and I had a new BullShadow slide to test so more soonish.
I forgot my bags on this trip too - doh!
I will point the mic at my ugly mug next time when I test 198 flatlines over H1000.
As far as that Twist Rate Calculator, it would be nice if there was an tickbox for copper solids. How do you guys normally adjust starting loads for solids? I normally pick the same weight as a lead core and just start on the lower end.
have a great week, its about to rain for days her in the south...
Anyway.. the rain started coming in and I had a new BullShadow slide to test so more soonish.
I forgot my bags on this trip too - doh!
I will point the mic at my ugly mug next time when I test 198 flatlines over H1000.
As far as that Twist Rate Calculator, it would be nice if there was an tickbox for copper solids. How do you guys normally adjust starting loads for solids? I normally pick the same weight as a lead core and just start on the lower end.
have a great week, its about to rain for days her in the south...
I've been able to find advice one place or another. With Flatlines, I've gotten good info from Warner, etc. I study manuals and get clues there too.
Hey All,
I’ve been off for awhile, work, travel, family etc…. But now just coming back to figuring out my load for my practically still new custom 300 prc barrel. I’m running an 30” Heavy Varmint Bartlein 9tw (they were out of 8 when I ordered) with a custom throat spun up by Patriot Valley.
Anyway I’ve shot a bunch of various powders prior to this new barrel but I’ve ultimately landed on using h1000, Lapua brass, and Berger 220 LRHT.
I’ve done a bunch of internet searching and found everything from 75.8 to almost 80 grains as recommended Goldilocks loads. I’ve seen book loads all over the place too and even run a bunch of sims in GRT.
Question here. Anyone else running these components and powder and if so what is your empirical data? My thought ultimately is to do a 0.2 single shot ladder from 75.6 to 78.4 and find flat nodes, then work on validating and groupings and seating from there. The spread just seems really wide here!
Thanks!!
Here is the new girl too!
The top one in the first pic. The lower is my 6.5 cm.
I’ve been off for awhile, work, travel, family etc…. But now just coming back to figuring out my load for my practically still new custom 300 prc barrel. I’m running an 30” Heavy Varmint Bartlein 9tw (they were out of 8 when I ordered) with a custom throat spun up by Patriot Valley.
Anyway I’ve shot a bunch of various powders prior to this new barrel but I’ve ultimately landed on using h1000, Lapua brass, and Berger 220 LRHT.
I’ve done a bunch of internet searching and found everything from 75.8 to almost 80 grains as recommended Goldilocks loads. I’ve seen book loads all over the place too and even run a bunch of sims in GRT.
Question here. Anyone else running these components and powder and if so what is your empirical data? My thought ultimately is to do a 0.2 single shot ladder from 75.6 to 78.4 and find flat nodes, then work on validating and groupings and seating from there. The spread just seems really wide here!
Thanks!!
Here is the new girl too!
The top one in the first pic. The lower is my 6.5 cm.
I run that exact combo. I ended up at 77.9gr because I have to run 3.625" to fit my standard AICS magazine. Started to have heavy lift at 78.5 so settled at 77.9 and it shot great there anyways.
Ran it over the AB radar at the ELR match and it showed 2915fps. G7 BC .375
Ran it over the AB radar at the ELR match and it showed 2915fps. G7 BC .375
I’m rolling with a 30” 9 twist SAAMI chamber using 225 ELD-Ms over 77.2 grains of H1000 going 2947 fps…very accurate load
Damn that BC is higher than book value: 0.369!
Awesome! Thank you sir! And that cooking!
Question for the masses.
I am doing my load dev with the h1000 today and got a hard lift bolt and pressure signs for my first round, ie lowest charge. It was a slow velocity that I’d expect from the lower charge and nothing else showed signs of high pressures even other rounds at the same charge weight or rounds at nearly 3 grains higher.
All the brass was treated the same as well, same annealing, same resizing etc. So what about that SINGLE round or piece of brass would have caused that?
I am doing my load dev with the h1000 today and got a hard lift bolt and pressure signs for my first round, ie lowest charge. It was a slow velocity that I’d expect from the lower charge and nothing else showed signs of high pressures even other rounds at the same charge weight or rounds at nearly 3 grains higher.
All the brass was treated the same as well, same annealing, same resizing etc. So what about that SINGLE round or piece of brass would have caused that?
Charge weight? Virgin brass? Barrel length? Velocity? Do you have a saami chamber or the AW2? If it is previously fired brass what die?
30” Barrel, custom throat from PVA, that I’ve seated for and shot a least few hundred rounds through at this point, with the same 220 Berger LRHT bullet and same Lapua brass but with different powder. Charge weight was 75.6.
Bras had 5 previous firings and annealed and full length resized… I’m kind of at a loss for the cause. Like I said the other rounds at the same charge had no signs. The rounds up to and including 78.2 had no signs either….
Carbon ring in the throat, possible am I trimmed piece of brass that is crimping the bullet when it bottoms out in the chamber or the unfortunately common PRC chamber issue. Most likely a carbon ring. But if you get clickers now that you are at 5 reloads it might be the tight chamber. A google search for “300 PRC clicker” will give you all the info you need. I would reach out to PVA and see if the reamer is based off the AW2 or if it’s SAAMI if you are for sure it isn’t a carbon ring and your brass is trimmed.
Question...since this was your very first round....did you leave just a little bit of cleaning fluid or oil in the barrel? If you have any moisture in your barrel...ie some liquid cleaner....left kroil in there...whatever...this is an uncompressible liquid that will cause a spike in pressure on even a modest load....especially on a July day.
#2 is possible but I highly doubt since you aren't running an excessively light load...but for the sake of discussion....if you put too little powder in your magnums....and it's a fast powder.....when the round is laying on its side in the chamber...the powder doesn't cover the entire flash hole. This allows the flame from the primer to flash across the entire column of powder and cause an increase in pressure that is WAY too high. Too little powder in a load can cause a catastrophic failure of your firearm and most people don't know this.
I would bet you had some oil or something in your chamber and caused that very first round to be high pressured. You can kiss that primer pocket goodbye....into the ole recycle bucket.
#2 is possible but I highly doubt since you aren't running an excessively light load...but for the sake of discussion....if you put too little powder in your magnums....and it's a fast powder.....when the round is laying on its side in the chamber...the powder doesn't cover the entire flash hole. This allows the flame from the primer to flash across the entire column of powder and cause an increase in pressure that is WAY too high. Too little powder in a load can cause a catastrophic failure of your firearm and most people don't know this.
I would bet you had some oil or something in your chamber and caused that very first round to be high pressured. You can kiss that primer pocket goodbye....into the ole recycle bucket.
Thanks for the info! Honestly I think I know why it happened but I can’t be sure since it’s after the fact but long story short it was possibly a stupid reloading error on my part.
That said that last part you pose is really interesting! Is it has there been any ballistics papers written about the phenomenon?
And this is why I follow this member. Strait to the point and easy to comprehend.
I’m guessing liquid vs vapor density during compression?
Subject: Barrel life of a 300PRC
So way back when we first started this thread, we asked and mused about the expected barrel life of this new cartridge that could push a 200+ grain bullet 3000fps. This is my third barrel on the 300PRC. I've been pulling at around 1500 rounds. My current barrel I haven't pulled yet because I'm awaiting my custom reamer to play with a 7-300PRC. Depending on the test I will either convert my Lapua 300PRC over to 7-300PRC or I will wash my hands of it and get a new 300PRC barrel spun up. The process of getting a custom reamer ironed out on specs, getting it made and delivery to my gunsmith is taking longer than I anticipated and I've been increasing the round count beyond what I thought I would have.
So, below is a picture of a group I shot this past weekend at TVP in a 1 mile benchrest match. The other 2 targets I shot that day did not have 5 on for a scoreable target because I didn't guess the wind correctly on a few shots and had some sail off the target due to a wind gust that I didn't see. This current barrel now has right at 1600 rounds on it. The highest on on the target could have been the 5th shot with increased speed due to heat on the barrel; but upon reflection I believe it was caused by not shooting in the same lighting condition...ie....the sun was popping in and out of the cloud cover. For those that don't know...optically the target can move from where you see it...and can cause up to 1 MOA of shift from behind a dark cloud to sunny. Anyway, enough excuses:
Yes....'not in the bullseye'....but at 1 mile...being a tad off on your sighters and you get no feedback to where you are hitting the target. I was very proud of my wind calls on this target. Wind was very strange. Flag behind the 1 mile berm was dead. I had 3.2 mils of left on the scope. The previous target I had 0.8mils of right on the scope.
My load has been ironed out for several years:
75.0 grains of RL-26
Lapua brass
Berger 245gr EOL
Fed 215M primer
Bullet seating depth of aligning the boat tail junction of the bullet with the neck/shoulder junction of the brass. This means it will not fit in my CIP length magazine but I single feed for benchrest and ELR matches.
I hope this information is helpful to some.
So way back when we first started this thread, we asked and mused about the expected barrel life of this new cartridge that could push a 200+ grain bullet 3000fps. This is my third barrel on the 300PRC. I've been pulling at around 1500 rounds. My current barrel I haven't pulled yet because I'm awaiting my custom reamer to play with a 7-300PRC. Depending on the test I will either convert my Lapua 300PRC over to 7-300PRC or I will wash my hands of it and get a new 300PRC barrel spun up. The process of getting a custom reamer ironed out on specs, getting it made and delivery to my gunsmith is taking longer than I anticipated and I've been increasing the round count beyond what I thought I would have.
So, below is a picture of a group I shot this past weekend at TVP in a 1 mile benchrest match. The other 2 targets I shot that day did not have 5 on for a scoreable target because I didn't guess the wind correctly on a few shots and had some sail off the target due to a wind gust that I didn't see. This current barrel now has right at 1600 rounds on it. The highest on on the target could have been the 5th shot with increased speed due to heat on the barrel; but upon reflection I believe it was caused by not shooting in the same lighting condition...ie....the sun was popping in and out of the cloud cover. For those that don't know...optically the target can move from where you see it...and can cause up to 1 MOA of shift from behind a dark cloud to sunny. Anyway, enough excuses:
Yes....'not in the bullseye'....but at 1 mile...being a tad off on your sighters and you get no feedback to where you are hitting the target. I was very proud of my wind calls on this target. Wind was very strange. Flag behind the 1 mile berm was dead. I had 3.2 mils of left on the scope. The previous target I had 0.8mils of right on the scope.
My load has been ironed out for several years:
75.0 grains of RL-26
Lapua brass
Berger 245gr EOL
Fed 215M primer
Bullet seating depth of aligning the boat tail junction of the bullet with the neck/shoulder junction of the brass. This means it will not fit in my CIP length magazine but I single feed for benchrest and ELR matches.
I hope this information is helpful to some.
Another question for the masses.
I’ve looked a few places and ran searches but curious to the “new thinking here”.
I’m running a 30” 9tw barrel and my normal load is w 220 LRHT w h1000 at 78gr running at 2910 roughly. I have some n570 laying around and some 245 EOLs…. Anyone work up loads with this combo recently? With similar stats?
I’ve looked a few places and ran searches but curious to the “new thinking here”.
I’m running a 30” 9tw barrel and my normal load is w 220 LRHT w h1000 at 78gr running at 2910 roughly. I have some n570 laying around and some 245 EOLs…. Anyone work up loads with this combo recently? With similar stats?
I have a load of 78.5gr for N565, N568, and N570 with the 245 EOL. I prefer RL-26...but my backup load is 78.5gr of N565...since I have a good bit of it. Speeds are 2900+ in my 30" 9tw Bartlein.
Similar threads
