300 Win Mag 215 gr. Berger N570

[Ladd]

I'm starting this thread for those that are interested in the 300 win mag loaded with the 215 gr Berger Hybrid with Vihtavuori N570. This is intended to be a companion to the thread "300 PRC 215 gr. Berger N570" (link to follow) but it can also be used as a comparison between the two. Many think the 300 PRC is superior to the 300 win but is it?

The data I'm posting in both threads are from almost identical Christensen Arms Ridgeline rifles. Both bedded in a McMillan Game Hunter stock. Both have the Christensen Arm's titanium side discharge muzzle brake. Both have the TriggerTech Special trigger set at 1.5 lbs. And both have Nightforce NXS 5.5-22x50 MOAR scopes on.

The only difference between the two rifles are the barrels. Both are 26-inch. The 300 win is 1:10 twist. The 300 PRC is 1:8.

300 PRC 215 gr. Berger N570

I wanted to start a thread for the 300 PRC with the 215 gr. Berger Hybrid. Not to prove anything but for a source of information. I'll be posting what I've done and note what I've seen in my Christensen Arms Ridgeline. Here's a link to a similar thread for the 215 gr Berger Hybrid with N570 but...

www.longrangeonly.com

 

[Ladd]

To be fair I'm using Hornady brass for my 300 win mag for this test because that's about all that is available for the 300 PRC, at least for another month. I have ADG and Gunwerks brass for my 300 win and I'm on the list for the run of ADG brass for the 300 PRC. Better get on it yourself. I'm also using the same primers, Federal GM215M primers. And the same lot of N570.

The reason I'm using N570 in my 300 win mag, for this test at least, is because that's what I've chosen for my 300 PRC, good or bad. I would like to see a comparison between the two rounds with almost every variable identical.

 

[Ladd]

I loaded the first rounds at 0.005 OL, 3.664 COAL, to test for pressure. Right off the bat I could cycle the rounds from my mag box. Couldn’t do that in my 300 PRC. And the depth appears to be almost perfect with respect to the case neck.

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[Ladd]

Not reloading with this combination before I started low (as everyone should) at shot #1 or 75.6 gr at 2855 fps and worked up in 0.3 gr increments. I worked up slowly over the next 2 hours letting the barrel cool even though it was 36 deg. F. I made it to shot #20, 81.3 gr at 3044 fps the first day and ran out of rounds. I loaded up seven more and went back out. At shot #21, 81.6 gr I saw a very faint ejector marks which hit 3055 fps. Shot #22, 81.9 gr I saw a faint ejector marks again (the Ridgeline has two plungers), no swipe or noticeable change in bolt lift. Shot #22 hit the high mark of 3104 fps and again only faint ejector marks. I shot two more after that and stopped with increasing signs of pressure. Shot #23, 82.2 gr was 3074 fps and shot #24, 82.5 gr didn't register on my Magnetospeed V3.

ADG or Gunwerks brass would be better suited. I'm not confident in the Hornady brass. However, I will continue from here backing off a grain or more from 81.9 and start seating depth testing.

 

[Ladd]

Here’s the 300 win mag with the 215 seated at 0.005 OL next to my 300 PRC with the 215 seated 0.065 OL.

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[fraz01]

Are both these rifles saami spec chambers ? Great thread, thanks

 

[Ladd]

Are both these rifles saami spec chambers ? Great thread, thanks

Yes. Both are SAAMI spec chambers. I haven’t modified them from the factory.


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[Broz]

Great thread and very valuable info for a question often asked. Thank you Ladd

 

[elkguide]

Thanks for allowing us to follow along. Anxiously waiting your continued testing.

 

[Ladd]

I compiled the data I gathered from the 300 win mag pressure testing and put it in spreadsheet form. For comparison I inserted the data from my 300 PRC testing. You can see that I didn't start each test at the same charge but you'll see how interesting the data is when side by side.

The 300 win mag was started at a lower charge but immediately it was producing higher velocities than the 300 PRC. The 300 win mag beats the 300 PRC at each charge in terms of velocity and interestingly enough the 300 win mag was the first to see pressure signs. The 300 PRC could take a larger charge before hitting pressure but the 300 win mag tapped out with a higher velocity than the 300 PRC.

 

[Broz]

Very cool data. So in this instance anyway, it kind of kicks a little dust on all this new technology "More efficient" case design stuff. At least thats what I get from it and the reason I guess I have always found my way back to the 300 win

 

[Ladd]

One interesting note from my testing. The first six rounds resembled the results I got from testing a box of Berger ammo with the 215 gr. Berger Hybrid. Many know how good the Berger factory ammo can be. One could use the low end of the spreadsheet above and get similar results. Probably better results, there are some good long nodes at the bottom there. The Berger factory ammo shoots 1/2 moa out of my Ridgeline and come with great brass.

Berger Ammo	Reloads
ES = 63	ES = 44
SD = 20	SD = 19.5
Ave. Velocity = 2866 fps	Ave. Velocity = 2874 fps

 

[gpowell]

The PRC is a bigger case, of course your going to have to use more powder to generate the same pressure/velocity. Using Quickload to determine the OBT on average the PRC will run 50-80 fps faster with the same chamber pressure and burn 2-3 grains more powder.


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[Broz]

Yes, there is roughly 2% H2O capacity difference in the two and that is a small amount I say. But , to me at least, this does shine a little light on all the publishing claiming "efficiency" The bottom line here is these two rifles will be running very closely at their accuracy nodes, and the win mag, at least in this case, may even be faster.

 

[Ladd]

This pic shows the two rounds at 0.005 OL next to each other and next to the 215s. I tried to line them up the best I could. The 300 win is already in a good depth position compared to the 300 PRC and the 300 win already cycles through my mag box here.

This hints to me that the 300 PRC may be more suited for heavier, longer bullets that shoot close to the lands like the load I have for it with the 230 gr. Hornady Atip.

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[Ladd]

One more picture. This is a graph of the data in the spreadsheet above. I took both cartridges to max pressure, maybe a round or two too far to be honest. Again, this was for max pressure testing with the bullet seated 5 thou off. I'll back off the 300 win charge a bit and start at 10 thou off and look for as good (accurate and as fast as possible) of a load as I can, just as I did for my 300 PRC listed in that thread.

 

[Broz]

That bullet seating comparison pic shows the PRC with it's slightly shorter case is running more freebore. So yes possibly to suit it for bullets with more bearing surface. I don't think I would want to run a 215 there with only about 50% of the bearing surface in the neck. Longer bearing surface / heavier bullets will be slower. Interesting to see what a fine tuned load in each. 300 win / 215 and 300 PRC / 230 would look like ballistically at a max hunting distance of 1200 yards to compare droft and drop.

It has added free bore for a couple reasons maybe, longer bearing surface bullets, or the Weatherby / RUM approach at adding velocity.

 

[Ladd]

That shows the PRC with it's slightly shorter case is running more freebore. So yes possibly to suit it for bullets with more bearing surface. I don't think I would want to run a 215 there with only about 50% of the bearing surface in the neck. Longer bearing surface / heavier bullets will be slower. Interesting to see what a fine tuned load in each. 300 win / 215 and 300 PRC / 230 would look like ballistically at a max hunting distance of 1200 yards to compare droft and drop.

That would be. I was very excited about the 300 PRC load I have with the 230 gr Hornady Atip until I read many of the field reports from the 2019 fall season. I still have many loaded up ready to go, thinking of giving them a shot at something this fall, find out for myself.

The load I have for my 300 PRC with the 215 is at 0.065 OL which looks really good with respect to bearing surface.

I thought when I've found a load for the 300 win I can take them both out to 500-1400 yards and see how they compare.

 

[Broz]

I find it interesting that I hear all the time that the shorter PRC is more forgiving to shorter mag boxes from its shorter case. But a PRC SAAMI reamer has so much more freebore it negates that claim.

 

[AveryMoonshine]

230 Berger 300 PRC 3.695. Just another picture for comparison.


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[Broz]

That would be. I was very excited about the 300 PRC load I have with the 230 gr Hornady Atip until I read many of the field reports from the 2019 fall season. I still have many loaded up ready to go, thinking of giving them a shot at something this fall, find out for myself.

I think I didn't like what I saw because I was simply sending the 230's into warp II velocities. I would hope that slowing the MV down 300+ fps would produce more favorable results. I have always stayed away from tipped bullets for this reason (except lathe turned solids) I agree more testing would be good before drawing a hard line in the sand.

 

[Ladd]

230 Berger 300 PRC 3.695 .010 off. Just another picture for comparison.


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That’s a good picture. You can see the 230 is seated better than the 215 close to the lands. Thanks.


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[gpowell]

Yes, there is roughly 2% H2O capacity difference in the two and that is a small amount I say. But , to me at least, this does shine a little light on all the publishing claiming "efficiency" The bottom line here is these two rifles will be running very closely at their accuracy nodes, and the win mag, at least in this case, may even be faster.

The only reason it's faster is because it's running at a higher pressure. Run the PRC at the same pressure and it will deliver faster velocity. Yes you'll burn more powder to get there. The only substantiating case of the PRC being more effiecient is that bullet takes up less case volume in a saami chamber.

I run a 300 win and have no reason to switch now but for someone buying an off the shelf rifle shooting factory ammo the PRC makes some sense.


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[Broz]

The only reason it's faster is because it's running at a higher pressure. Run the PRC at the same pressure and it will deliver faster velocity.
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If I am understanding this correctly, I have to question it. What I mean is, one one hand you are saying the win mag is showing faster velocities because it is creating more pressure at a lower charge weight. I am not disagreeing with this at all. I think we agree that pressure is where velocity comes from. But on the other hand you say the PRC needs more powder to equal the velocity of the 300 win mag but will create more velocity at equal pressure. I am sorry but I tend to disagree. To explain why. The case volume is so close I don't see that as much of a gain. Brass manufactures will have a larger tolerance from one to the other than 2% in some cases. And if like barrels with like bullets and like powder burn rates have the same pressure, they theoretically should produce the same muzzle velocity. In my opinion, difference in velocity in these two chamberings will be more to do with one barrel possibly being faster than the other.

I am not putting down the PRC at all. My point is they are very close to the same and will preform very close to the same all things equal. Some barrels will always be faster than others. But for sure I do not see all the marketing claims portrayed in some PRC advertising.

 

[Ladd]

I tried and measured a box of 300 PRC Hornady 212 gr. ELD-X, a box of 225 gr. ELD Match and a box of Berger Ammunition 300 win mag 215 gr. Hybrid. The best 3-shot group I got from either of the Hornady boxes was 0.70 moa. The best I got from the Berger ammo was 0.51 moa. Each of them were accurate and I don't doubt a shooter could buy any one of these boxes and do well in the field. I keep a box or two of each on hand just in case.

ELD-X 212 gr.
2977 fps ave. velocity
53.7 SD
112 ES

ELD Match 225 gr.
2903 fps ave. velocity
26.5 SD
96 ES

Berger Ammo 215 gr.
2866 fps ave. velocity
20 SD
63 ES

 

[Dave Wilson]

The only reason it's faster is because it's running at a higher pressure. Run the PRC at the same pressure and it will deliver faster velocity. Yes you'll burn more powder to get there. The only substantiating case of the PRC being more effiecient is that bullet takes up less case volume in a saami chamber.

i agree with gpowell, this has been my thoughts while reading this post. i bet if you could use the same amount of powder and shoot the same bullet from a 30-06 and a 300wm, the 30-06 would show more velocity. a smaller chamber burning the same amount of powder will make more pressure. or maybe I just think that because i'm building a 300PRC! lol

 

[Broz]

i agree with gpowell, this has been my thoughts while reading this post. i bet if you could use the same amount of powder and shoot the same bullet from a 30-06 and a 300wm, the 30-06 would show more velocity. a smaller chamber burning the same amount of powder will make more pressure. or maybe I just think that because i'm building a 300PRC! lol

We are not talking that much of a difference in case volume between the win and PRC as the win and 30-06. Again I believe the 2% or 1.5 grain of capacity is a mute point and can easily be lost from one brass mfg. to another.

Pride in ownership is a human trait we all have to some degree. The 300 PRC is in no way a bad thing. When quality brass comes around it will be a lot better choice than I feel it is today. But I can easily add a touch of free bore to a 300 win mag, and run at safe pressures at or faster than a 300 PRC. Not much, and again the barrels will more likely dictate the velocity difference. But the PRC simply is just the product of good marketing.

There are things I need to test further before I debate other tributes of both. But that all will come in time.

For now I am rebarreling from a 30 N to a 300 win mag (custom reamer on both) and I feel I have done enough homework to stand by this decision.

Due to more freebore in the SAAMI 300 PRC I do see where it could be a better choice for 230 gr bullets. Than a SAAMI 300 win mag. But I don't think the lost velocity and more BC will beat the 300 win mag / 215 combo at distances we will be taking elk at.

Just my thoughts after much testing.
Jeff

 

[Broz]

I find this testing interesting, and also find these conversations valuable. It is all part of the journey to find real world data. So thank you all for the discussion.

I also have done some very extensive testing on other things that attribute to what we use as pressure indicators. I am here to tell you simple things like chamber wall finish can take a rifle that is showing an ejector mark and has increased bolt lift resistance and change it into a rifle with no ejector mark and no bolt lift just like that. And still no ejector mark or bolt lift after an increase of 10 grains of charge weight of / 6%. I tested this on two rifles that exhibited the same results. One I had the same barrel off 6 times, changing chamber wall finish, and tested until the point of gains were no more. I will add I had a very well versed smith helping me along this path and he gave me some very valuable lessons.

The point is there will almost always be variables in testing. But good conversation can lead to knowledge to make good decisions.

Jeff

 

[Ladd]

I guess I’m not getting the points about pressure. Sure I understand it and how more pressure relates to higher velocity but.

I took each cartridge up to what I thought was max pressure with the 215 seated at 0.005 OL in both rifles. Ejector marks and gas out the primer pockets was a sign that I was close and I didn’t dare take either any higher. The 300 win mag gave me a higher velocity in this area.

Maybe when the ADG brass for the 300 PRC comes I could try to run it up again. I’d have to do the same for the 300 win mag. I don’t think it would go much higher. I was surprised how much the Hornady brass took.

Either way I need to move on to seating depth testing at specific charge weights and see if I can find a nice accurate load. I’ll comment on that when it’s through and note what I settle on and compare it to what I settled on for my 300 PRC.


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[AveryMoonshine]

I tried and measured a box of 300 PRC Hornady 212 gr. ELD-X, a box of 225 gr. ELD Match and a box of Berger Ammunition 300 win mag 215 gr. Hybrid. The best 3-shot group I got from either of the Hornady boxes was 0.70 moa. The best I got from the Berger ammo was 0.51 moa. Each of them were accurate and I don't doubt a shooter could buy any one of these boxes and do well in the field. I keep a box or two of each on hand just in case.

ELD-X 212 gr.
2977 fps ave. velocity
53.7 SD
112 ES

ELD Match 225 gr.
2903 fps ave. velocity
26.5 SD
96 ES

Berger Ammo 215 gr.
2866 fps ave. velocity
20 SD
63 ES

I broke my 300prc barrel in with Hornady 225 ammo but due to my Chronograph not working I was never able to retrieve any velocities also the gun hated them. So I moved on to 212 Hornady ammo. My average velocity’s are nearly identical but accuracy is lacking with them. best 3 shot group to date of 1.250 today with Average Velocity of 2986 and single digit ES for the 3 shots. I appreciate you sharing your experience with the cartridge(s)fun to be making my own at the same time and comparing. Also feel these tests seem to reveal that even though it’s “old” “crusty” “out dated” and still wearing that antique 108yr/old belt the 300WM is no joke and clearly works.
All good conversation
Enjoy


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[Ladd]

Looking at the data I have in this thread for my 300 win mag I was thinking of backing off to 81.3 gr. and test seating depth from there. What would you do?

I also decided to eliminate another variable going into looking for a good load by putting a Nightforce NXS 5.5-22x50 C433 on my 300 win to match my 300 PRC.

 

[Broz]

Looking at the data I have in this thread for my 300 win mag I was thinking of backing off to 81.3 gr. and test seating depth from there. What would you do?

I also decided to eliminate another variable going into looking for a good load by putting a Nightforce NXS 5.5-22x50 C433 on my 300 win to match my 300 PRC.

I do think there could be a good load there around 81.0 to 81.5. With 570. 3K to 3050 is a nice velocity too. I would bet it will shoot between touching and -040" off the lands. Dan Glover has a sweet load for his new 300 win /215 with H-1000 at 3020 from a 26" but with a custom reamer.

 

[Ladd]

I thought the data showed a decent flattened spot in that area too.

 

[DoubleGobble00]

The velocity I get from my 300 win mag has always impressive me. I can get 3040 FPS with 215 Bergers and no pressure using N570. In fact, I could probably only get another 100 FPS more with my 300 Rum which would take a lot more powder. The 300 win has really impressed me.

Great thread... only thing I like about the 300 PRC is the neck design. It might have less need to trim but I trim all the time anyway.

 

[Ladd]

The 300 win mag rounds have been loaded for the seating depth testing. 0.005-0.035 OL with 81.5 gr N570 215 Berger Hybrids.

With the help of my RCBS Matchmaster the powder was kept to 81.48-81.50 gr. I’ll shoot these looking for a 1/2 moa group or better.

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[Ladd]

I compiled the data I gathered from the 300 win mag pressure testing and put it in spreadsheet form. For comparison I inserted the data from my 300 PRC testing. You can see that I didn't start each test at the same charge but you'll see how interesting the data is when side by side.

The 300 win mag was started at a lower charge but immediately it was producing higher velocities than the 300 PRC. The 300 win mag beats the 300 PRC at each charge in terms of velocity and interestingly enough the 300 win mag was the first to see pressure signs. The 300 PRC could take a larger charge before hitting pressure but the 300 win mag tapped out with a higher velocity than the 300 PRC.
View attachment 4296

Proof that my 300 win mag hit 3100 fps with the 215 gr Berger.

Range day tomorrow.


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[Dave Wilson]

IBirch said, The 300 win mag beats the 300 PRC at each charge in terms of velocity.

of course it will, it's physics. just like the 30-06 with less powder will beat the 300 win mag in terms of velocity.

 

[Broz]

of course it will, it's physics. just like the 30-06 with less powder will beat the 300 win mag in terms of velocity.

Can I see the actual test data, between a 30-06 and 300 win mag in the same type of test done here with like components and rifles to support this statement please? I am not sure a broad statement like that has me convinced since the capacities of the cases you used for the example are quite a bit different in capacity where the PRC and Win Mag are almost the same capacity. And in some cases, dependent on brass used, the 300 PRC and 300 WM could be the same capacity.

I totally understand "the Physics" and how it effects the velocity, but don't agree with using extreme examples to represent two cases that are so very close in capacity will apply.

To further expand on this. I would like to see the data for a 30-06 and 300 win mag both using a like powder like H-1000 or N570 (for example) in like brass and a 215 Berger. We all know the 300 win mag is going to win unless we alter the test components to show otherwise. But the PRC and WM being about as close as we can get in capacity makes the test data in this thread as solid as I have seen between two cartridges of different case design but like in capacity.

 

[AveryMoonshine]

lbirch.. since you have a pretty good load with the PRC and 230 aTip would be interesting to see how the 2 compare in that situation. Probably be for a different thread but I’d be curious to see the results.


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[Ladd]

lbirch.. since you have a pretty good load with the PRC and 230 aTip would be interesting to see how the 2 compares in that situation. Probably be for a different thread but I’d be curious to see the results.


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That would be. I do like the load I have with the 230 gr. A-tip. I haven't thought about anything other than the 215 in my 300 win but why not.

 

[AveryMoonshine]

That would be. I do like the load I have with the 230 gr. A-tip. I haven't thought about anything other than the 215 in my 300 win but why not.

300wm and 215 seem to be a near perfect match. Just seems to me the PRC is maybe more suited for the slightly heavier bullets. Seems only fair for comparison to try it.


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[Ladd]

300wm and 215 seem to be a near perfect match. Just seems to me the PRC is maybe more suited for the slightly heavier bullets. Seems only fair for comparison to try it.


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Definitely a valid argument, I think I agree. Maybe I'll have to burn more powder this winter. I have a pretty good stockpile, and a full box of atips.

 

[Ladd]

Here’s a quick update from a brief range visit this morning. I watched a heavy 4-pt buck feed over the ridge 250 yards away when I got there, I love big mule deer bucks. A good sign if you believe in that sort of thing.

After a couple fouling shots and to get it near zero since I just mounted the new NXS, I started on the loads in 35 deg weather. It didn’t take long.

I’ll have to take the Magnetospeed out to test for the other numbers. I wanted to make this post without waiting.

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[Broz]

Definitely a valid argument, I think I agree. Maybe I'll have to burn more powder this winter. I have a pretty good stockpile, and a full box of atips.

Ladd, I would be glad to send you some A Tips if you need them. I have some I will not be using. The least I can do for your great work on all this.

 

[Broz]

Here’s a quick update from a brief range visit this morning. I watched a heavy 4-pt buck feed over the ridge 250 yards away when I got there, I love big mule deer bucks. A good sign if you believe in that sort of thing.

After a couple fouling shots and to get it near zero since I just mounted the new NXS, I started on the loads in 35 deg weather. It didn’t take long.

I’ll have to take the Magnetospeed out to test for the other numbers. I wanted to make this post without waiting.


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I am guessing that load is a bit over 3K. Maybe 3050 ish

 

[Ladd]

I am guessing that load is a bit over 3K. Maybe 3050 ish

Yes sir, I think it will land in that neighborhood.

 

[Dave Wilson]

Broz said, Can I see the actual test data, between a 30-06 and 300 win mag in the same type of test done here with like components and rifles to support this statement please? I am not sure a broad statement like that has me convinced since the capacities of the cases you used for the example are quite a bit different in capacity where the PRC and Win Mag are almost the same capacity. And in some cases, dependent on brass used, the 300 PRC and 300 WM could be the same capacity.


you can, go to the Hodgdon reloading center. find the velocity for a 30-06 with H4350 powder pushing a 180 gr ball. the velocity is 2798 using 57.5 gr of powder.
the 300 win pushes it 2787 using 63 gr of powder. the 30-06 pushes it a tad faster with 5.5 gr less powder. i only looked at one powder, i'm sure there are several, but this explains the physics behind the why

the quote from my last post was the 300wm beats the 300prc at each charge in terms of velocity. i'm simply pointing out why that is and giving an example that is more extreme as sometimes it's easier to see when an example is exaggerated. i am in no way suggesting the 30-06 will push bullets faster than a 300wm, but the same charge will develop more pressure, aka speed, in a smaller chamber.

the 300prc and wm are much closer in capacity but i'm sure the 300prc will edge out the wm in velocity all things being equal.

 

[Broz]

the 300prc and wm are much closer in capacity but i'm sure the 300prc will edge out the wm in velocity all things being equal.

Ok, Thank you. I disagree and my proof in in this thread. It takes a bigger increase in volume than 0 ~ 1.5 grains (brass dependent) of powder to act as you are suggesting.

Jeff

 

[Ladd]

Broz said, Can I see the actual test data, between a 30-06 and 300 win mag in the same type of test done here with like components and rifles to support this statement please? I am not sure a broad statement like that has me convinced since the capacities of the cases you used for the example are quite a bit different in capacity where the PRC and Win Mag are almost the same capacity. And in some cases, dependent on brass used, the 300 PRC and 300 WM could be the same capacity.


you can, go to the Hodgdon reloading center. find the velocity for a 30-06 with H4350 powder pushing a 180 gr ball. the velocity is 2798 using 57.5 gr of powder.
the 300 win pushes it 2787 using 63 gr of powder. the 30-06 pushes it a tad faster with 5.5 gr less powder. i only looked at one powder, i'm sure there are several, but this explains the physics behind the why

the quote from my last post was the 300wm beats the 300prc at each charge in terms of velocity. i'm simply pointing out why that is and giving an example that is more extreme as sometimes it's easier to see when an example is exaggerated. i am in no way suggesting the 30-06 will push bullets faster than a 300wm, but the same charge will develop more pressure, aka speed, in a smaller chamber.

the 300prc and wm are much closer in capacity but i'm sure the 300prc will edge out the wm in velocity all things being equal.

Looking at Vihtavouri's reloading data, a 30-06 pushes a 215 at 2625 fps with a max charge of 50.6 gr N560. Data for the 300 win doesn't go as low as 50.6 gr but for a 63.9 gr min charge of N560 the 300 win mag pushes the 215 at 2533 fps. The 300 win has less velocity in this case. However, the 300 win obviously catches and surpasses the 30-06 with a max charge of 70.4 gr N560 at 2779 fps.

The powder capacity of the 300 win and 300 PRC are close but different by about 2 gr where I stopped at max pressure testing in each rifle. I could push the envelope of the 300 PRC's pressure maybe but I stopped each test with similar pressure signs. The 300 win mag pushed the 215 faster at every data point faster than the 300 PRC up until it pressured out. The 300 PRC kept going with a larger charge until it maxed out at nearly the same velocity but less none the same.

The 300 win mag doesn't win because it has a higher velocity at max. I think the winner will be which ever one has the more accurate load at the highest velocity. I'll soon find that out for myself.

 

[Dave Wilson]

IBirch said, The 300 win mag doesn't win because it has a higher velocity at max. I think the winner will be which ever one has the more accurate load at the highest velocity.

i agree with this 100%