Peterson 300 winmag brass review

Supersubes

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  • Sep 6, 2006
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    While at the SHOT show this year, my friend Daniel and me spent a good amount of time in the Peterson Cartridge booth speaking to the owner, Rick Peterson. We were interested in what they had for a few reasons. More sources of brass is always a plus, but their cartridge selection looks like is was polled from hide members. They offer .308, .308 Palma, .260, 6.5 Creedmoor (in two neck thicknesses, coming soon),300 WM .338 lapua, and both Cheytacs. I believe they're working on 300 Norma as well, although it's not listed on the site yet. Their prices are very reasonable as well. What was most impressive about them though, was how eager they were to hear customer feedback, which is kinda strange for a brass manufacturer. If anybody is using their stuff currently, don't hesitate to forward your feedback to them. They want to compete with the best, and are willing to make production changes to get there. My friend Daniel obtained small quantities of a few different cartridges. I'll detail our experience with the 300 WM here. At this point, our testing is not finished, but posted here for the good of the community. For the record, I have no affiliation with Peterson and I'm a huge Lapua fanboy. I'll gladly pay Lapua money for my brass, but Peterson's prices are hard to ignore. The winmag brass we tested here, sells for $41 per 50 cases. That places it just above the standard domestic brass, and below Hornady/Nosler. One other cool thing they do, is they ship the brass in high quality MTM style see through cartridge boxes. These have really deep lids, so they actually fit the loaded cartridges with the heavy/ long bullets most of us here use. I hope they continue this practice!

    Daniel did all the loading and shooting. The rifle is a R&D precision custom, which uses a 26" Bartlein 5R in 10 twist. I don't have specifics on the Chamber dimensions, but It's R&D's "match" reamer, and works very well with domestic 300WM. Mag length in a AICS mag puts you .006 off the lands in this chamber with a 208 ELD, and all test loads were loaded to that length. The Peterson brass functioned flawlessly through the gun throughout our tests.

    The load used 208 ELD's at 3.638 OAL, Peterson brass, H1000, and 215M's. None of the components were sorted or trued in any way. Brass was simply FL sized, chamfered, and loaded.

    We fired two OCW tests. The first one was fired in the desert at 535 yards. It unfortunately was inconclusive, as Daniel experienced some serious vertical dispersion issues. I believe this was due to a less than ideal shooting position. I was able to obtain before/after belt expansion numbers though, as well as the velocity data. We re-fired the exact same test just a few days ago at 205 yds, with much better results(see below). Historically, this rifle has always shot

    The water capacity of the Peterson brass is approximately 2% less than that of Hornady or Winchester brass. If you plan to try this brass, I'd recommend you back your existing charge off approximately 2 grains and work up.

    Water weights:
    The weights below are from fired cases out of the test rifle.
    Peterson 90.7 gr
    Hornady 92.3 gr
    Winchester 92.7 gr

    I took before and after belt diameter measurements using a .0001 graduated blade mic. My mic is dead on, and I calibrate it regularly. These numbers should be viewed from a comparative standpoint though. They may not match yours, but what's important is the growth before and after of my measurements. Brass was allowed to return to ambient temps before they were measured a second time. If you aren't familiar with the method, Hodgdon details it here. http://www.hodgdonreloading.com/rel...-trick-monitoring-pressure-your-rifle-reloads. I believe their numbers are conservative. I've observed some cases grow far more than what they advise, without no ill effects. It's pretty straight forward though to correlate your results with the other signs of pressure you're seeing. I like this method as it just paints a more complete picture of pressure. Instead of re-writing these results, I'm posting them in pics below.

    Daniel loaded 74.5-76.5 grain charges, in half grain increments, and reported no sticky bolt throughout the test. I saw no ejector marks during measuring. All velocities were obtained using a labradar. Daniel threw his charges from a Hornady auto charge, which I think is contributing to his extreme spreads. The node still showed itself, but future tests will have charges checked on a second scale. I'd also like to test seating depths, as I think that would further lower his spreads. One thing I can't report on yet is durability of the new brass. We've only just gone through the batch once. I'll be back to post those results when we have some.


    Enjoy!

    https://www.petersoncartridge.com/

    http://rdprecision.net/

    http://www.hodgdonreloading.com/rel...-trick-monitoring-pressure-your-rifle-reloads
     

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    Supersubes, thanks for this post, look forward to the results regarding the durability of the Peterson brass. A friend has been very impressed with their .375 brass, 4 firings so far and primer pockets are still tight as new. Considering their 338 lapua brass..........
     
    I have the 338 brass in hand. I plan to run them side by side with some virgin lapua to see how they stand up. I'll post results. Should have preliminary results in about two weeks.

    That will be a great test! Lots of "hiders" will be interested in that type of test I think. Prior to your results, it might be interesting how the weights (and the consistancy of the weights) compare. In a box of the Peterson 375's all were within 1.5 grains which considering how big the cases are is pretty impressive. In comparison, my lapua cases vary by 4 to 5 grains within a lot and up to 7 grains between lots. I'm hoping the Peterson 338's can improve on that a bunch.
     
    I had a less than positive experience with my 308 Peterson brass. After 2 & 3 firings on two lots of 100, I was still experiencing significantly more neck & bullet runout and less accuracy than my Norma brass. I email Peterson and got no response. I then neck turned half and got another firing or two on them with little improvement. I emailed Peterson again with no response. The brass is sitting on the shelf waiting for me to figure out a solution.
     
    I had a less than positive experience with my 308 Peterson brass. After 2 & 3 firings on two lots of 100, I was still experiencing significantly more neck & bullet runout and less accuracy than my Norma brass. I email Peterson and got no response. I then neck turned half and got another firing or two on them with little improvement. I emailed Peterson again with no response. The brass is sitting on the shelf waiting for me to figure out a solution.


    Thats weird, they've been really responsive to us. I'll see what I can find out.

    Was the issue caused by neck wall thickness variations?
     
    Thats weird, they've been really responsive to us. I'll see what I can find out.

    Was the issue caused by neck wall thickness variations?

    It was a couple months ago but from memory neck turning improved the runout. I don't recall the specifics after neck turning but it was still not what I had come accustomed to with Norma brass. Looking through my sent box, the emails were sent on October 2nd and November 4th of 2016.
     
    QUOTE=L.R.Novice;n6394497]

    It was a couple months ago but from memory neck turning improved the runout. I don't recall the specifics after neck turning but it was still not what I had come accustomed to with Norma brass. Looking through my sent box, the emails were sent on October 2nd and November 4th of 2016. [/QUOTE]

    My friend Daniel spoke to Peterson this morning. If anyone is having issues with Peterson brass, they want to know about it. The point of contact is below.

    Joe Coury,
    Director of Development
    [email protected]
    (724) 940-7552 X204
     
    How much do the cases weigh?

    918v, my buddy just got back to me with this.
    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/uploads.tapatalk-cdn.com\/20171117\/cb9b3c3fefdb209e42659c8cf5c1118f.jpg"}[/IMG2]



    Cases are holding up well. Like all of their stuff we’ve tested so far, the cases are very stout, especially the primer pockets.



    Sent from my iPhone using Tapatalk
     
    918v, my buddy just got back to me with this.
    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/uploads.tapatalk-cdn.com\/20171117\/cb9b3c3fefdb209e42659c8cf5c1118f.jpg"}[/IMG2]



    Cases are holding up well. Like all of their stuff we’ve tested so far, the cases are very stout, especially the primer pockets.



    Sent from my iPhone using Tapatalk

    That's pretty consistent for 300WM.

    Do they expand at the belt like eurobrass or ahead of the belt like American?
     
    That's pretty consistent for 300WM.

    Do they expand at the belt like eurobrass or ahead of the belt like American?


    The batch is only three firings in, so its hard to say. Daniel is a working gunsmith, and busy, so always another project that needs working out. He is equipped with a die for dealing with the area above he belt if needed, but he hasnt had to use it. Something that seems to be consistent with peterson is high overall hardness, especially in the case head. The pockets flat out dont budge. Someone here reported (maybe in this thread or one of my other tests) they they enlarged the pockets on their WM brass. I find that hard to belive personally, but not impossible.

    I posted the belt expansion numbers in a picture. Looks like the pic is broken or something. Are you not seeing it either? Its in my notes if not.
     
    It's not coming up.

    But casehead expansion at the belt is obvious. The belt looks like the forward half of it expanded bigger than the back half. American brass expands differently in that the belt remains unaffected but the case walls .020" or so ahead of it bulge.
     
    It's not coming up.

    But casehead expansion at the belt is obvious. The belt looks like the forward half of it expanded bigger than the back half. American brass expands differently in that the belt remains unaffected but the case walls .020" or so ahead of it bulge.


    I’ll dig it out of my notes. There wasnt anything abnormal, and I seem to recall about .001 or so at the belt.

     
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    I first found Peterson a few moments ago looking for casings for my next rifle that shoots 300 Norma Mag... (Peterson never even showed up in ammoseek.com results :( Then I did a search for reviews and found this thread. Good stuff. Thank you for posting.

    I went looking to buy .300 win mag casings thru their outlet https://www.grafs.com/peterson-cartridge-company but I can not find. Have they discontinued .300 wm? I did find best price on bulk .300 norma mags. Yay! Peterson Brass 300 Norma Mag Unprimed Bulk Box of 250 only $489.99
     
    I first found Peterson a few moments ago looking for casings for my next rifle that shoots 300 Norma Mag... (Peterson never even showed up in ammoseek.com results :( Then I did a search for reviews and found this thread. Good stuff. Thank you for posting.

    I went looking to buy .300 win mag casings thru their outlet https://www.grafs.com/peterson-cartridge-company but I can not find. Have they discontinued .300 wm? I did find best price on bulk .300 norma mags. Yay! Peterson Brass 300 Norma Mag Unprimed Bulk Box of 250 only $489.99


    I was told a couple of weeks ago by Peterson that their 300WM brass should be available again in a couple months. Not sure what the delay is all about.