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21 Bullseyes
isn't this a m60 tank? Vietnam era? sorry im bit lax in my military hardware…
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105 Bullseyes
How much recoil do you feel was reduced with the Vais brake? Did it come with the threads to match your CTR?
Maybe about a 30% reduction in recoil…its a perfect balance right now! hardly any barrel jump. Great improvement for the range. The brake indexed perfectly with the barrel…just need to snugg it up pretty tight. Worked perfect with the factory threads…
One thing I will add is they are right when they say its the “quietest” brake design…My buddies were saying it has no noticeable noise increase when we shot it this weekend. Unlike the brake I have on my 300wsm, that thing makes the gun handle like a 223 but it's really loud!
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1 Bullseye
I went out today, shooting off front & rear bag very little wind.
168gr BTHP Hornady Best Group .560
ZQi Nato Brass 2.005
Coal 2.865 .020 off lands
Varget 45.5gr
2708 FPS150gr FMJBT Hornady Best Group .700
ZQi Nato Brass 2.005
COAL 2.800
IMR 4064 45.6gr
2779 FPS -
105 Bullseyes
Looks like the 168 load is coming together…my groups really started to get tight around 46+ grs…
What was your SD on the reloads? -
105 Bullseyes
No problem…its one more thing you need to know for accurate loads and drop charts.
SD = Standard Deviation…you input the data of say 10 shots of your reloads and you get the average difference in velocity averaged over 10 shots…the lower the number the better for accurate reloads. Its makes a huge difference if you are shooting long range.
Here's a link to a quick calculator, just input your chronograph numbers for 10 shoots and calculate.
https://www.easycalculation.com/statistics/standard-deviation.php
Some of the better chronographs measure this for you, you just need to surf through the menu.Copied from the web…
The chronograph measures the velocity of your bullet (or arrows, pellets, etc.) as it travels through the sensors, in feet per second (fps)and will also record the number of shots, the high velocity, the low velocity, extreme spread (ES), the average velocity, and standard deviation (SD).
The “high” reading shows the fastest shot, the “low” reading shows the slowest shot, the “average” gives you the average of five shots or ten shots ( called the shot string or ‘string’). The extreme spread (ES) is the fastest shot minus the slowest shot.
The (ES) goal for the long distance hunter should be within 30 fps or better. And 20 fps puts you at the beginning of competitive benchrest shooting. There is also standard deviation (SD) which is the measure of how close each shot’s velocity in the shot string will be to the “average.” For the long-range marksman, 9 to 12 fps is good. The lower the (SD) the better. -
1 Bullseye
I ran 2 strings shot on different days
Day 1 SD of 25.70
Day 2 SD of 11.93
Combined days 23.47Combined average FPS 2721
What would you consider a good SD to work for?
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105 Bullseyes
Those aren't bad numbers at all…single digits are rare, but anything under 20fps is perfect. But thats a difficult task as well. Here's something that has helped me since i've started reloading.
I work brass in groups of 50, and I weigh / sort bullets. I use 1 set of 50 sorted brass for all my target shooting till I start getting split necks, enlarged primer pockets, or too short…this may be any where from 5-10+ reloads depending on caliber and brand of brass. When I get 5-10 cases in the set with these issues I toss the bunch and start over with a another sorted set of 50…I never load 100's of rounds or anything like that for a specific load unless it varmint hunting. And I never mix reloaded brass, meaning…I never mix reload #5 brass with reload #1 brass…Always working the same set of 50 brass cases. I picked 50 specifically because of the MTM ammo cases. I have about 200-300 rounds in MTM boxes on the shelf fully prepped and sorted for each of the 3 calibers that I regularly shoot, 308 / 300wsm / 223…this simple thing improved the quality of the reloads I make. Its easy after that, trim brass, prime brass, fill cases, press bullet…control every factor you can.
I've got a couple loads now that are holding a 20SD or better, Varget & H4831sc powders are mostly responsible for that…best powders for my guns
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1 Bullseye
I am also working on a .223 68gr BTHP Hornady
PMC Brass 1.750 Case
Benchmark 23.8gr ( a little heavy bolt @ 24.1 real heavy bolt @ 24.5 )
Fed primer
Coal 2.235
FPS 2780 -
105 Bullseyes
If you have a chance to try Varget, load a few cases with 25.3-25.7grs (somewhere in that range) with that bullet. You should be around 3000fps…out of a Tikka Lite or Varmint barrel. You won't be disappointed, trust me!
I shoot a 60gr Nosler BT Spitzer over 25.5grs of Varget and its sub MOA out to 500yrds if wind isn't blowing too hard…3100fps out of my 223 Varmint. Super accurate load.
CFE223 worked will in my 223 as well but I only shoot this powder in the summer… 26.7grs and a Nosler 55gr BT Spitzer = 3200fps…Does this to clay targets at 400+ yards. I glued this one back together to keep on my reloading bench. One of the best cold bore shots I've made to date….only 1/2″ off at 420yrds accounting for wind. That does not happen everyday.
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105 Bullseyes
I have 2 versions, both are great.
223 / 300wsm – Vortex Viper HSLR FFP 6-24 x 50
308 CTR – Vortex Viper 6.5-20 x 44 -
1 Bullseye
I thought I'd throw my info on to this thread.
LH Tikka Sport in .308, 24″ barrel. Trigger is adjusted to 1.7 lbs. Scope is Minox ZA 5 5-25 x 56 tac. Leupold PRW rings on an inexpensive 2 piece steel base (can't remember the manuf) while I wait for my 1 piece from the tikka performance boys to get their batch finished.
After running out of varget, I ran tests using H335, of which I have 3 jugs. Using 168 AMAX in lapua brass, I ran some ladder loads using at 40.8, 41.2, 41.6, 41.9, and 42.1 gr all at 2.805 OAL, 5 rounds each.
At 100 yards, calm day, off the bench with harris bipod and rear bag, all of the loads shot extremely well. Every target was well under 1 MOA, with groups averaging about 5/8″. I loaded up my next batch at 41.4 and my results at 100, 200 and 300 yards were excellent, with groups going under 1 MOA. I'm very pleased with these loads and the rifle is a definite gem.
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1 Bullseye
Dog,
I ran 2 loads of .223 68gr BTHP, 23.6gr & 23.8gr Benchmark Powder 7 shots each to find the SD.
23.6gr avg FPS 2852 SD 10.12
23.8gr avg FPS 2843 SD 18.17You were correct the lower SD grouped better, I was amazed how .2gr made a difference.
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105 Bullseyes
Thats great, I'm assuming no pressure signs yet? How were the groups?
I've had really good accuracy with this bullet using other powders but I have some Benchmark on the shelf that I may have to try, thanks for the load data.Here's a chart showing what your drop looks like with 23.6gr of benchmark.
Really good out to 400yrds – 500yrds…but then starts dropping fast.http://www.shooterscalculator.com/ballistic-trajectory-chart.php?t=3cfedbd3
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