tallburnedmidget wrote:Nice work! Too bad about the not staying subsonic thing. In any case can you tell us:
-How far out you shot the hog at? (was it 17yds?)
-What you did to ensure a good shot was being taken? (marked off area, range finder, etc.)
-Prep work you did for the subsonic challenge?
-How much did the Subsonic Primer Hunting thread help?
-What did you learn that you did not expect?
[EDIT: Just noticed you also posted in the Subsonic Hunting Primer Thread, editing to request the answers be posted there instead of here.]
I know, lots of questions here but I am very curious and the answers really help build our knowledge when it comes to subsonic hunting. Please post the answers in the Subsonic Hunting Primer Thread
http://300blktalk.com/forum/viewtopic.p ... 6&start=10 .
Thanks
-How far out you shot the hog at? (was it 17yds?)
-What you did to ensure a good shot was being taken? (marked off area, range finder, etc.)
It was 17-yards. I was sitting in a tree stand about 15-feet high and I ranged all the entry and egress points in the area with my new
Leupold RX-1000i TBR with DNA Digital Laser Rangefinder (~$400 USD Amazon) so I knew the distances I would be likely shooting at. I also knew the angles I was shooting down at but at such close distances they wouldn't add perceptibly to the bullet drop.
The biggest concern for me was the very close distances and
Sight Over Bore height of 72mm (2.84-inches) for my
Trijicon ACOG TA11F (3.5x35mm) scope (~$1,000 online) on a
LaRue Tactical ACOG Mount QD LT100 ($135).
At that 17-yards my Point of Impact would be 1.0-inch lower than my Point of Aim on the scope, but luckily it would stay at ~1-inch all the way to ~70-yards, which was the furthest distance I had a clear shot, but which was much too far away to even attempt to shoot when a bit of patience would result in the hogs getting a lot closer. Most of the likely points where I would see a hog were within 20-yards and a few were within 10-15-yards. Point blank distances and I only had to remember to aim 1-inch higher.
-Prep work you did for the subsonic challenge?
Without talking about the multi-year whole weapon, scope, suppressor selection process I basically have an
Lewis Machine & Tool (LMT) AR-15 originally as a Piston 16" (also with 16" Gas Stainless-Steel, 12" Piston, 10.5" Gas barrels in 5.56mm) registered as a Short-Barrel Rifle (SBR) and now their
LMT 10.5-inch 300 AAC Blackout/Whisper barrel with a Pistol-Length gas system. I have the newest
SureFire SOCOM762-RC FDE 7.62mm (30-Caliber) 8.3" suppressor (~$2,000 with Price, Tax, NFA Stamp, S&H) and
SureFire SFMB-762-5/8-24 muzzle brake to be used as a quick-attach adapter.
(I'd never again voluntarily shoot an SBR 10.5" or 12" with a muzzle-break without a suppressor, the sound shock produced is uncomfortable with -33 NDR rated hearing protection directly behind the gun, much less on the side. Shot it once, never again.)
I created a custom load for my gun after reading this thread, certified's load data, and many other threads on this forum and watched YouTube videos regarding loading for 300 AAC Blackout cartridge with
Accurate 1680 powder and the highly recommended
Lehigh Defense Maximum Expansion 194gr All-Copper Pre-Cut bullet ($77 + S&H x 50 bullets).
I created a load ladder of 5-cartriges loaded with A1680 using 11.0 to 11.8gr with 0.2 increments and chronoed them with my
MagnetoSpeed V2 ($380) chronograph. The results were 11.0 = 930, 11.2 = 1,020, 11.4 = 1,049, 11.6 = 1,075, 11.8 = 1,123.
I found that 11.4gr produced a velocity of 1,049fps and seeing other manufacturer's (
Lehigh Defense 1,040fps) who make subsonic loads advertise that their subsonic ammo is 1,050fps I settled on that as my target speed. I checked the
Speed of Sound calculator which is 1,116fps at Sea Level at 65F so I had 66fps leeway and shooting at 125ft Above Sea Level at ~50F temperatures would be 1,106fso this would keep me well under it.
(That's what I though and I was wrong, my load went supersonic on me, for the 2-shots fired, and 2-shots fired back at camp.).
I referred to
Lehigh Defense's Load Data for my handloading numbers for Accurate 1680 powder for a 10" SBR barrel and their starting load was 12.0gr going down to 11.7gr to achieve a velocity of 1,050FPS. My chronograph originally predicted 11.4gr = 1,049gr the previous week, but on Saturday my results for a 10-shot string shot with the 11.4gr produced average velocity of 1,006fps, Standard Deviation 22fps, Extreme Spread 75fps, Minimum 970fps, and Maximum 1045fps. So about 45fps lower than the target 1,050fps. My load of 11.4gr was 0.3gr under the bullet manufacturer's recommended load so I felt comfortable that it would perform well and stay subsonic. (It went supersonic during the hunt.)
I also used the invaluable
QuickLoad software to develop
my load data calibrated for my rifle's barrel and chamber with attention paid to the AR magazine length (2.260" + .004" for Magpul PMAG Gen 2 Window), fire-formed Nosler 300 AAC Blackout cartridge H20 overflow volume of 24.30gr of water for subsonicly fired cases at ~28,000psi, Accurate 1680 powder burn rate of 0.6415Ba from the uncalibrated 0.8050Ba, 60F temperature, case height 1.360", and bullet measurements Length 1.516" +-0.010".
I used the accompanying QuickTarget and transferred the gun and load data into it from QuickTarget's custom handload data. I created
graphs for a 50-Yard Sight-In distance to show me the Line of Bore, Line of Sight, Line of Target for this specific load so that I was aware of the Sight-Over-Bore height and how it affects my shot-dope for closer and further distances than my sight-in distance.
My Point Blank Range Zero is all the way out to 84-yards using a 1.57" (4cm) height of the default Vital shot area with a 1-inch drop all the way from 17-yards to 68-yards, which were almost the exact distances that I would be taking the closest and furthest shot at. Easy to remember a 1-inch drop. Closer than 10-yards the sight-over-bore distance of 2.83" inches starts coming into play so for close-quarter shots I had to remember to aim 2-3-inches higher.
(My load of 11.4gr that was subsonic the day before at the range for a 10-shot string at 1,006fps @ 60F @ 125ft ASL went supersonic the next day at 50F @ 320ft ASL. I pulled the bullets out and weight the charges checking for over-chrage user error on my part but the powder was all 11.4gr exactly so this was another issue. Currently investigating variables.)
-How much did the Subsonic Primer Hunting thread help?
I helped immensely, I used it as a guide for my experience along with a lot of other threads and posts that I read for about a month straight to familiarize myself with learning to handload and about the 300 AAC Blackout cartridge, subsonic reloading, powders, gas systems, bullets, and also about hunting hogs, subsonic expectations, bullet selection for proper expansion. That's how I learned about Lehigh Defense's Maximum Expansion bullets that I chose as my go-to round for subsonic hunting to guarantee reliable expansion and ethical kills on animals with minimal amount of suffering and quickest method of dispatching and expiration.
I did a lot of research on hog anatomy, optimal shot placement, distances of average encounters, and other strategies helped me understand and prepare for the staged hunt and further hunting and stalking on public lands or large private lands.
-What did you learn that you did not expect?
1. That a targeted 1,049fps load that choronoes a little slow at 1,006fps the day before as subsonic can go supersonic with a loud sonic crack the next day during the hunt and make me scratch my head in puzzlement and feel a bit embarrassed in front of the land owners and my friends who were concerned that someone else was shooting on their property because they weren't expecting me to shoot that day nor to hear my shot if I did have to shoot if my two friends didn't bag their 2 hogs.
2. That subsonic hunting works just fine and the performance of the subsonic loads with a PBR Zero of 84-yards is quite plenty for hunting most medium size game animals such as hogs and deer and others.
3. That subsonic hunting with a suppressor and not having to wear hearing protection only eye protection is an enjoyable pleasure to commune with nature and the sounds of the woods and the wild (or at least someone's fenced in hog wildlife refuge property.)
4. That doing tons of research and knowing the exact details before making handloads and the predictions using QuickLoad and QuickTarget software for your load and sight graphs is invaluable and takes a lot of guessing and trial-and-error out.
5. That reading and learning from other people's experiences including successes and mistakes can save you a lot of time, money, and frustration by doing things that work and skipping things that don't.