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300wspr

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Reply with quote  #1 
I'm am new to 277 not to reloading. Looking for help from some one who has tried a similar load . My gun is a 10.5 inch 1:7 twist running suppressed only, wanting to load 95 grain mdws copper hp over imr4227 with cci41 primers. Loaded some at 19.5 grains primers came out and on third round case got stuck. I have looked on load data posted cannot find any that are 10.5 1:7 twist any one who could chime in I'd appreciate it
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RedRaider

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Reply with quote  #2 
Not a current sub reloader , but most folks here and elsewhere load subs with 150 gr bullets or heavier. So you probably will not find data on sub 95 gr bullets, but I've been wrong before. Best of luck and post data if it works for you.
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RangerJoe

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Reply with quote  #3 
300WSPR - Are you trying to run subsonic with the 95gr MDWS copper slugs?  Also, are you confident that the brass you used wasn't too short in term of case/cartridge headspace?  Have you measured the difference in case headspace between your fired brass and loaded ammo? 
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300wspr

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Reply with quote  #4 
Sorry I left out an important piece of information- I was to run supersonic through a supressor.
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RangerJoe

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Reply with quote  #5 
300WSPR.  If you go to the .277 WLV Load Data pages and search on 4227 (http://mdws.forumchitchat.com/?forum=393087), you'll find lots of folks testing & running 4227 with various bullets and barrels.  Don't worry if you have a 10.5" barrel and only find data for 8.5" and 12.5"... that little bit is insignificant.  You are running a can, so pressure will be higher than without.  What I saw is lots of data indicating 19.5gr with a 95gr bullet should not have been blowing primers and leaving cases stuck in the chamber.  I suspect something else is the main problem.

Before you load more (lower charge weight) test rounds, I really suggest you confirm your cartridge headspace.  Excess sizing of the brass when forming Wolverine from 5.56x45 can leave the case too short (headspace - not OAL) and that can cause blown primers and/or ruptured cases.

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300wspr

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Reply with quote  #6 
Thanks for the reply I will check the brass tonight
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300wspr

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Reply with quote  #7 
How much difference does the 1:7 twist barrel make as far as pressure vs the 1:11 twist
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Dvalin

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Reply with quote  #8 
Quote:
Originally Posted by 300wspr
How much difference does the 1:7 twist barrel make as far as pressure vs the 1:11 twist

None, or at least not enough to notice in MY experience.

Edit****Always start low and work up your load, your experience may be very different from mine*****
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300BLK

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Quote:
Originally Posted by Dvalin
None, or at least not enough to notice in my experience.

So why is there a warning at the bottom of the load data chart?
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Dvalin

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Reply with quote  #10 
Quote:
Originally Posted by 300BLK
So why is there a warning at the bottom of the load data chart?

It's always wise to be cautious, and start low and work up your load for any new barrel. The faster twist barrel certainly has the potential to build pressure sooner, but I have not had that experience.
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300BLK

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Reply with quote  #11 
Quote:
Originally Posted by Dvalin
It's always wise to be cautious, and start low and work up your load for any new barrel. The faster twist barrel certainly has the potential to build pressure sooner, but I have not had that experience.

I got ya. Has anyone seen a noticeable difference in 1:7 versus 1:11 firing lightweight supers?
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MDWS

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Reply with quote  #12 
Quote:
Originally Posted by 300BLK
So why is there a warning at the bottom of the load data chart?
That was there from when we first launched the 1:7 Twist barrels. Those bottom three warnings in red should be deleted at this point.

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RangerJoe

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Reply with quote  #13 
Quote:
Originally Posted by 300wspr
How much difference does the 1:7 twist barrel make as far as pressure vs the 1:11 twist
From a purely engineering/scientific point of view, there MUST be some difference.  Taken to extremes - a zero twist barrel (with lands and grooves) will have less resistance than a 1:1 twist barrel having the same dimension lands and grooves. The question becomes one of degrees.

None of our testers have noticed "significant" or "concerning" pressure increases going from 1:11 to 1:7, especially with shorter barrels.  I have not tested 1:7 WLV, so I have no personal experience, but lots of our experts have.

I do have experience in scientifically testing 5.56x45mm NATO M16 barrels of various twists.  With a 20" barrel, there was a significant pressure increase and loss of accuracy when firing M193 Ball Ammo going from 1:12" to 1:7".  However - the bore was smaller, the barrel longer, and the ammo loaded to max pressure.

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bbbrownfield

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Reply with quote  #14 
That's one of the things we'll learn when Mark has test barrels with sensors on them to track such things as pressure along the barrels length. I shoot a 16 inch 1:7 barrel and have a 20 inch 1:7 on order, I regularly shoot 90gr bullets with no problems even though they are spinning their heads off. But it takes more pressure to push them down a 7 twist barrel than an 11 twist, a function of rifling angle and drag and a longer distance- 1:7 has longer rifling than 1:11 per inch of bore length. Those test barrels are going to allow these guys to track it all.
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300wspr

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Reply with quote  #15 
Thank for the replies I loaded a few more with 1680 gonna try that instead of 4227
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300wspr

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Reply with quote  #16 
Ok had improvement with 1680 loaded 21.0 grains and had no primer issues or stuck cases however the accuracy was horrible now I just need to run a ladder
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Airaddict

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Reply with quote  #17 
Heres my ladder for 110 vmax and hornady HPBT using 1680.

Kinda weird groupings. 2 consistently would be close and one shot opened up the group. Very light swipes started showing up at 21.1 on the vmax, and the 21.4 on the HPBT.

The only exception is the 20.4gn sighter on the vmax target. The low shot was my first, and i adjusted the scope 1.25" up. The second and third shots fell into the same hole.

On the HPBT, There is clearly a velocity node between 19.5-20.5. Seems to peak around 20.2. The sighters at 20.4 shot well as predicted from another member.

On the VMAX, the velocity node seems to be between 20.3-21. Prob gonna peak around 20.5. Unfortunately only one sighter at 20.4 read correctly on the chrono, but it matches the HPBT velocity.

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kshunter

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Reply with quote  #18 
Guys I need some help, the research portion of my brain isn’t working. I’m looking for load data on the new MDWS 95, has anyone posted results yet? I’d like to get some tested for my sons savage axis wolvy.

Thanks 👍🏼
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BIGGDAWG

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Reply with quote  #19 
Quote:
Originally Posted by kshunter
Guys I need some help, the research portion of my brain isn’t working. I’m looking for load data on the new MDWS 95, has anyone posted results yet? I’d like to get some tested for my sons savage axis wolvy. Thanks 👍🏼

I have shot it and posted some data with 1680 and shooters world blackout.  24 grains of shooters world is safe max 23.5 is safe max with 1680 from my testing. don't start there - drop 10% and work up

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RangerJoe

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Reply with quote  #20 
I still need to get some of those 95 grainers!  My youngest son will be hunting with the 18" 1:11 WLV I built him using 90gr GDs this year.  I'll take my 18" WLV (1:11) and 18" x40 (1:12).  We are hunting some hilly juniper pines... unlikely to get any shots beyond 150 yards.
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