New PRS rifle for old benchrest shooter

[El Viejo]

I think you're putting a little too much focus on your load and maybe overlooking several things you will need to learn to unsuck at starting out.

Not surprising, with your shooting background. Nonetheless, your first few matches will show you without question that spending time on the perfect load was time wasted.

Learn it now the easy way or later the hard way.

Pirate:

When trying to get a handle on new stuff or a new sport like PRS, I have a tendency to focus on what I know a little bit about and then expand to the great unknown. Getting a decent load for shooting little tiny groups is something I have done for a number of years. Naturally, that's an easy place to start for me. I decided to go for the 6 GT as the cool new kid on the block. That will be an interesting challenge. Moving from 6PPC in a custom benchrest rifle to 6ARC in a gas gun that I built was an easy / fun transition which I did last fall in time for deer season. An MOA of +/- 1.0" is plenty good for a deer size critical zone out to at least 300 yards. I also got to try all sorts of impromptu supports.

Working up the hunting loads also allowed me to work with a number of new bullets that are not suitable for 6PPC. I fairly quickly found that my AR-15 "liked" the Berger 95 gr and Hornady 103 gr ELD-X a lot better than the 108 gr ELD. I am curious to see how the Berger 109 and the ELD 108 will do in a 6GT bolt gun. For me, PRS will provide new challenges in terms of quick position change, down range ballistics, and long range wind reading. The clock is just one more factor that I already deal with in IDPA, IPSC, and Steel Challenge.

I have a lot to learn, and I expect it will keep me busy for a couple of years and a couple of barrels. By then, I may get invited to sit at the kids table.

 

[308pirate]

Pirate:

When trying to get a handle on new stuff or a new sport like PRS, I have a tendency to focus on what I know a little bit about and then expand to the great unknown. Getting a decent load for shooting little tiny groups is something I have done for a number of years. Naturally, that's an easy place to start for me.

I understand that it's human nature. And it's still a mistake to focus so much on what you already have a handle on.

There's a good saying out there: practice what you suck at. You can turn that around to your situation by changing it to: focus on what you don't know much about.

But I could be wrong......

 

[El Viejo]

OP, you say you are an "old" BR shooter. Does that mean you're "old" chronologically, or "old" as in having played BR games for a couple of decades?

If it's the former, let me (as a near- septuagenarian) tell you straightaway: build your 6GT or buy a Tikka or whatever, assemble a 1/2MOA load, and practice positional shooting as much as your time, budget, and body will allow. Shoot through ladder rungs. Shoot off tops of 5-gallon pails. Start a 90-second timer, drop prone, shoot two, get up and move to a bench top, shoot two, repeat, at single targets or different-range targets using holdover. Transitioning from one prop to another eats up time. Simply working out how to hold my rear support bag and rifle when moving to or changing props was a big deal... How long does it take you to walk up to a bench or drop prone and get that first shot off?

I'm ate up with arthritis and have a damaged right leg with limited range of motion. The stages which require going prone and back up on the clock are very difficult... as are stages which force a lot of back-tilt of my head (again, arthritis). There is no way I'll ever come near the leaderboard in even one-day PRS matches, let alone regional or national matches. Last I heard, "senior" class starts at age 55, and my oft-repeated response to that is "calling a 55-year-old a senior is like calling an 18-year-old an adult." But I enjoy the competition environment, engaging different target sets, and doing the best I can. I work out ways of mitigating my physical limitations as best I can.

I think it's natural to gravitate toward shooting little tiny groups from comfortable positions (kinda like benchrest?). But PRS isn't that. I met a young, strong newbie recently who shot his first match earlier this month. He is capable of shooting consistent tiny groups from the bench... but he scored a bit less than 20% of the top gun's score and said to me afterward, "I gotta do that positional practice!"

Only a decade of serious BR. I will need a lot of practice on positions. Although my test firing area at home is only about 50 yards, it will clearly show what I can't do well and what positions really suck. Climbing in and out of heavy equipment or saddling a horse or hitching a team have kept me flexible. But definitely slow.

In addition, I can use the 1000 yard range at a local gun club. The local PRS group only does one match a month at this location. There's a much closer club that I joined for pistol, but the longest steel is 300 yds with very tricky winds.

At least for now, I am only interested in the physical and mental challenge not my place in the standings. That allows for a reduced stress level as a newbie.

 

[b6graham]

don't overlook a 22 for positional practice especially if you can shoot 50y at home

 

[camocorvette]

Well here's what I found out sitting at the kids' table...

This is what happened in the barrel I tested with, with the components I used. I'm not suggesting and can't guarantee you'll get the same results with your stuff in your rifle.

Latest Hornady manual publishes 40.3gr as the max charge for H4350 in the 6.5 Creedmoor with 147-153gr match bullets... So let's see how "Lawyer loaded" it is... "PeakA" is the peak pressure of the shot. SAAMI MAP is 62,000psi for the 6.5 Creedmoor. 55-65ksi is typical across the board for modern brass cased rifle stuff. These are all at 2.800" COAL.
View attachment 7852363

Oh... Turns out it's not pooched for the "litigious environment"... In fact, almost every time I've tested various book max loads in several different cartridges, they've been right at, if not slightly over SAAMI MAP.


Now let's go to the Sniper's Hide to find our good data... In fairness, I'm using a different bullet and case so results may vary a little, but it does raise an eyebrow.


I am curious how you know it's around 66ksi, though. I saw another mention in that thread from you stating that published load data is watered down. I really want to know what source you're getting that information from.
View attachment 7852364

And for shits and gigs I found another post in there with someone else (actually a couple people IIRC) loading up to 43.0gr of H4350 with a Hornady 147 and I only shot 1 because at this point I was a little afraid of damaging a transducer. Obviously the guy posting this also has "no pressure signs or hard bolt lift"...
View attachment 7852370


And now some rambling...
Hodgdon currently lists the 147 ELD-M + H4350 combination at 60,800 PSI at 41.8gr.
They list the 143 ELD-X + H4350 combo at 61,200 PSI at 41.8gr.

But the 143 is extremely similar in its external shape/dimensions to the 147, yet 4 grains lighter... They also list the 140gr class bullets at a max of 40.0-40.4gr...

Are they wrong? No. Probably not.

When they tested it, with the lot of powder, at the humidity level they tested it, that's probably exactly what their test barrel/system spit out.

Anyway, it goes to show that there is some lot-to-lot variation. That should go without saying-- any reactive chemical production is going to have variation-- not all 91 octane gas is the same, not all H4350 is the same. There is variation in chambers, bullets, cases, etc... You can certainly see a rise in pressure based on fouling levels. There are a multitude of reasons why the same ammo will produce higher or lower pressures, and those numbers move around a little with manufacturing of all of the components. That's why every reloading manual ever states to back down and work back up after changing any component........

The point I'm getting at is that the published data is (with rare exception) correctly acquired and truthful. This myth that it's "Lawyer loads" needs to die, right along with the phrase "No pressure signs", because it obviously extremely subjective. If you want to reference multiple manuals and game the game using the largest published charge weight you can find, whatever... But going multiple grains over published max loads is asking for trouble in pretty much every case. Using unverified, untested load data off of the internet is also a sketchy endeavor as far as I'm concerned. You'll have some guy telling you 44gr of Varget with 62g solids is hammering in his 22 Creed-- "No pressure signs at all"... lol

YMMV, your gun your face, etc... Hopefully this was informative.

Not a single pressure sign, then bam!

(Actually there was, I'm just retarded.)

 

[DownhillFromHere]

Only a decade of serious BR. I will need a lot of practice on positions. Although my test firing area at home is only about 50 yards, it will clearly show what I can't do well and what positions really suck. Climbing in and out of heavy equipment or saddling a horse or hitching a team have kept me flexible. But definitely slow.

In addition, I can use the 1000 yard range at a local gun club. The local PRS group only does one match a month at this location. There's a much closer club that I joined for pistol, but the longest steel is 300 yds with very tricky winds.

At least for now, I am only interested in the physical and mental challenge not my place in the standings. That allows for a reduced stress level as a newbie.

Sounds to me like you're good to go, with attitude, previous experience, and availability of practice and match venues all in your favor.

So indeed the best thing you can do is practice building a stable position on a variety of props, and quickly & smoothly transitioning from one prop to another.

Even the simplest of exercises is worthwhile - with support bag in one hand and rifle in the other, can I approach a prop like a barrel (on its end, on its side either parallel or perpendicular to line of fire, angled, etc) and drop onto it, with rifle supported and aligned with target, in one motion, with minimal or no wiggling around to adjust? The good shooters make it look so easy - they walk up, plop goes bag, plop goes rifle on bag, and Bang.

Good luck - enjoy.

 

[TripleBull]

I understand that it's human nature. And it's still a mistake to focus so much on what you already have a handle on.

There's a good saying out there: practice what you suck at. You can turn that around to your situation by changing it to: focus on what you don't know much about.

Great advice that many have difficulty following. Many people believe it's more fun to try to stick in a comfort zone. If you experience failure to improve and that doesn't piss you off enough to make you challenge your process, then go ahead and have fun.

I had a great mentor push me into a face-to-face confrontation with my weaknesses long ago. Initially, I was pissed off and had my little feelings hurt. Then I dealt with the brutal truth and got through a few more roadblocks.

 

[Kocher]

some pretty passionate fellows ...

why can’t you use the 6ARC gas gun for PRS first timer?

Or was it bench rest?