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Originally posted by offgrid:
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Originally posted by NikonUser:
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Originally posted by offgrid:
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Originally posted by NikonUser:
Thanks for the report, offgrid. I noticed that you did not give the most important datum on the barrel, the twist rate.

Also, I know this is going to expose me to ridicule here and get me banished from Wisconsin for the cheese festival but I'm not a fan of Brux barrels. I'm not saying that's the reason. Just a comment.

At any rate, if the barrel does not like the bullet, then you look for another bullet. I stop at 1000 yards anyway.

On the other hand, I am a huge fan of Kelbly's products.


9 twist.

So, has a Brux barrel out shot you in a match? Big Grin


A little slow, but that's not the problem, methinks.

As for Brux barrels, I'm sure they are fine now. I just have a long memory and I'm a big fan of Krieger barrels.

I've been beaten by all great brands of barrels, and I've beaten all brands of barrels.


Keep in mind our altitude. We do load work up at 5200' on the private range. Magnum match in Raton 6700' another match in Wyoming 7500'-8000'. My home ranges 7700' and 8500'.

Most everyone around me has or is shooting a 6BR. We have a saying when comparing calibers, loads... Is it BR (6BR) accurate? BR easy to tune? It shoots OK, it ain't no BR. My buddies 300PRC with the 225 ELD or 215 Hybrid is BR accurate.

I too been beaten by all the great brand barrels and have beaten them all.


Yeah, you seem to have quite an attitude problem. Oh, wait...

I live at sea level, which makes me a level-headed guy, instead of an air-head. Wink

I'll be on my way to Raton next month for the Nationals. I hope you don't suck up all the oxygen before I get there.

Highest elevation I've been to was Pike's Peak @ 14,100feet ASL. Heck of a drive up and driving down was worse.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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I had a match today where I was able to test the bullets at 1000 yards for 65 rounds. I am very impressed; I shot the bullets paying little attention to the wind and in 65 rounds all day, never shot worse than a 9 (inside 2 MOA at 1000 yards.) I really only aimed at the X or sometimes pulled a little to one side of the 10-ring or the other.

I was not shooting for score or to win so much as to try to see how the wind affected these bullets. The other folks were telling me they were holding a lot further out than I was and a bunch still collected some 8s.

I had some elevation issues but that was due to a total lack of case prep; the cases I was using were all brand-new, never been fired. For the September match, I will be using twice-fired prepped brass.

My large order for the bullets came in on Friday; I'm all set.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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I shot another match this weekend with properly prepared cases this time.

I'm still playing a little bit with the load but I was trying more for a good score on the first relays then on the third the wind really picked up.

This is where I discovered a couple of things. First off, let me say that I had been using the 210JLK exclusively for several years and I know the ballistics of that bullet well in my rifle. The ballistics of the 230 A-tip appear to be about 1/3 less wind displacement in similar conditions. I'm still trying to wrap my mind and my "muscle memory" around this; I found myself holding off more than needed at times and when I consciously forced myself to reduce the hold, I scored better. This will take some getting used to. I discussed the holds with another shooter who is a top competitor and he was using the Berger 200-20X, which he launches at 2650+FPS. His bullets get on target at about 1500FPS according to the Shotmarker. My bullets leave at about 2380FPS and get on target at about 1510FPS, also according to the Shotmarker. He was holding almost at the edge of the frame on the right, and I was still holding in the black. Our zeros are probably somewhat different but the difference in hold is staggering.

The delta-V is about 1100FPS for his bullets and it's 850FPS for the A-Tip; this is over 1000 yards.

I did lose some points to straight drops and I attribute those to gun handling. My thinking is that any mistake in gun handling will be magnified on the target because of the lower velocity. I have to hold higher on the target with these heavy bullets, by about 3 MOA, which represents about a 10% increase. This means my mistakes will be magnified by 10% on target, so I have to be as perfect as I can be. I had some nice strings going, like a 10 followed by four Xs only get an 8 straight down, and then continue with six 10s in a row, before getting smacked again. Need to not get cocky and shoot one shot at a time.

Nationals are in 10 days. Need to finish loading ammo and get on the road.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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It's been a while since I've been here, so I'll catch you up.

I loaded all my ammo in plenty of time for the Nationals. I drove up to Raton and was there for the week. I crashed and burned, and it was very apparent that I was ill-prepared to compete this year at the Nationals. I had very little experience with my ammo, I was tired beyond belief and the wind conditions were horrible. Also, my scorecard was not turned in on the second day. The team matches were horrible; the wind conditions were crazy and the folks who shoot there a lot were definitely favored.

For some reason, I was squadded on the low end all week, what is commonly referred to as the toilet. I had target 10, then 7, then 9. If you've been to Raton, you know what I'm talking about; in windy conditions, the unexplained verticals will bite you big time. The conditions were vastly different relay to relay and also according to the firing point you were on.

For example, on the second day of the individuals, (target 7), I was pulling targets for a good friend who shoots F-Open and was the national champion the year before. The conditions at our end were so bad, people stopped shooting for a long time, but only on our end. I could hear the fusillade going on at the high end. Those guys finished quickly whereas our side was plodding along. I had a train wreck on that relay and yet, I still outscored my F-Open friend. I never left the black, he visited the white area on the target; something I have NEVER seen him do in 10 years of competition. It was that bad.

On the final day of shooting, I was handed target 10, again; I was so pissed, I told them I did not want to shoot in the toilet again. They gave me a high numbered target. I was so out of contention, I had no compunction about raising a stink about the assignment. I should point out that the favored firing points are between 40 and 70. The 80s start getting more elevation issues, but nowhere as bad as the low numbers.

So I settled down to shoot as best I could for the last day, get some redemption. On my first shot, my bipod broke. I was unable to drive it properly so I resorted to squeezing the bag. I dropped some points at the start of the string and then when I resolved to squeezing, I shot much better. That was pretty much the story of my experience at the Nationals.

When I came back, I had time to get ready for the TSRA Mid Range match and I had lead another work party the weekend before the match to get the electronic targets ready. I rapidly loaded 200 more rounds for the match and I ordered another batch of A-Tips as I was running out.

I assembled a team for the Friday match and one of the guys brought a shotgun to a rifle match. I shot in the team match and I had a teammate call wind for me. He did an excellent job and I concentrated on marksmanship. On the last relay of the match, he had a bit of problem estimating the correction for the A-tips compared to his Berger 200-20x. After dropping 4 points at the start, he caught on and we cleaned the remainder of the string with 10Xs. He was pleased as I was. I really concentrated on my marksmanship and gun handling. I also borrowed his bipod while I was shooting. As luck would have it, my gunbuilder was our scorer when we shot that string. He was very impressed with what he saw.

During the weekend, I was heavily involved with match operations, helping people with etarget issues and could not concentrate on shooting like I wanted to.

On Sunday, I met up with my gun builder and we got to talking. I explained to him that the 230s required the shooting form to be perfect. If I bauble, I get weird results. I put that down to longer barrel time. My gunbuilder also reminded me that I have a 34inch barrel and he strongly suggested that it be cut back to 30 inches. The longer barrel time of the slower 230s is exacerbated by the longer barrel. It's like a minus on top of a minus.

At the end of the match, I left my rifle with him to cut the barrel down. Next time at a match in in November, so no shooting for a while.

I'll come back here shortly to discuss a few findings about the 230s and my load.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Sounds like a rough match!

I've seen plenty of discussion about trigger lock time impacting sensitivity to follow through and proper form, but never really thought about barrel dwell time causing the same kind of issues. Interesting!
 
Posts: 4889 | Location: TX | Registered: January 24, 2011Reply With QuoteReport This Post
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Originally posted by maladat:
Sounds like a rough match!

I've seen plenty of discussion about trigger lock time impacting sensitivity to follow through and proper form, but never really thought about barrel dwell time causing the same kind of issues. Interesting!


The word going around F-TR competition circles is that 230-class bullets have lots of unexplained verticals and the sweet spot seems to be around the 200gr bullet weight.

I have been using 210s for over 5 years and I kinda know how to hold a rifle, but I'm far from perfect on that, at least in consistency. And consistency is the name of the game in F-class.

Let's do some numbers. The lock time of a competition bolt action rifle is under 2ms (millisecond or .002 seconds). On an AR-15, the lock time of the standard trigger is about 8-9ms. Geissele introduced his speed trigger which brought down the lock time to about 4-5ms.

The barrel time of my 230gr load in a 34 inch barrel is 1.7ms. In an AR-15, the barrel time of a 77gr bullet in a 20 inch barrel is a fraction of that to the point that compared to the lock time, it can simply be ignored, which is why you've never had to consider it.

The targets used by F-class are much smaller than regular targets and the distances are longer; I shoot at 600 and 1000 yards. A 1MOA difference will take an X-ring shot into the 8-ring; it gets to the 9-ring in 0.5MOA.

One MOA is defined as Minute of Arc or Angle. There are 60 minutes in one degree and I have difficulty looking at an object to see if it's canted by one degree. The precision required is obnoxious and when you have a 17 pound rifle under full recoil with a very heavy bullet, a very fast twist, keeping the rifle pointed properly for 1.6ms after the 1-2ms of lock time becomes a challenge. This is where your form, your followthough becomes critical and it must be the same way every single time.

I realized my form is not perfect every time and I can tell when the shot is going to disappoint me. It's just easier to bauble a shot with the much heavier bullet.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Last week after the 600 yard match, I left my rifle with my gunbuilder. He did not put the rifle together originally, that was done by another gunsmith, also a competitor but not an F-class shooter.

My current gunbuilder cut 4 inches from the barrel and did a complete assessment of the rifle. It was built 7 years ago and is now on its fifth or sixth barrel.

He found that there was an issue with the firing pin fall. It's supposed to be 0.240 or more and mine was at 0.214. He explained that I needed to contact the action maker and get a new hanger, one with a 0.30 inch offset. I figured that a short pin travel could lead to misfires, but I wasn't getting any of those.

He explained that he discovered that a short firing pin travel can also affect the precision of the rifle. That was a new one on me and I asked him what the physics of that would look like. He was befuddled and be explained that while he did not know WHY it would adversely affect precision, empirical data showed him that a proper pin travel yielded better precision for every rifle for which he did the fix. It's an easy thing to replace so I contacted my action maker and asked them to send me a new hanger, just to be safe.

I should get it this week and I will install it on my action when it does arrive. My gunbuilder also stated that he had checked every other parameter and that the rifle was in great shape.

That's always good to hear after tens of thousands of rounds. To celebrate, I cleaned it thoroughly this past weekend, what with the Raton sandblast factory and the hot and humid 3 days of TSRA almost back to back, my rifle needed some babying. I even waxed the stock.

My gunbuilder and I further discussed the use of A-Tips. He's also starting to use them in other calibers and we swapped some findings about them. He also recommended that I seat my bullets differently and that I up my powder load and go chase the next higher up node.

I also received the part to fix my bipod and it is now back to pristine condition. Bring on the next match, but first, a ladder test to chase that higher node.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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The hanger came in today. I wiil do the swap out tomorrow. Looks pretty simple, but need to break out the torque screwdriver.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Originally posted by NikonUser:
I contacted my action maker and asked them to send me a new hanger, just to be safe.


What is the “hanger” you are referring to? (Internet search is of no help unless one wants something to hang a rifle on the wall.)

As for the issue of the firing pin travel, I am reminded of something I read decades ago about action jobs on S&W revolvers that reduced trigger pull weight by cutting or reducing the power of the mainspring. That of course also reduced firing pin impact force, and although shooters like PPC competitors were careful to not reduce the mainspring force so much as to cause misfires, there was evidently evidence that lower striking force did affect accuracy (or “precision” as we’d call it today). That was not something most handgun shooters would ever even notice, but it could make a difference when trying to hit the X-ring of a B-27 target at 50 yards.

I wonder if the effect of firing pin travel in a precision rifle could be a related phenomenon.




“The terror of the Roman arms added weight and dignity to the moderation of the emperors. They preserved peace by a constant preparation for war; and while justice regulated their conduct, they announced to the nations on their confines, that they were as little disposed to endure, as to offer an injury.”
— Edward Gibbon, The Decline and Fall of the Roman Empire
 
Posts: 40714 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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The best way to answer that question is to link to this video made by my friend Erik.

The hanger is the item that he removes from the action and on which he pins the Jewell trigger before putting the assembly back into the action.

https://www.bing.com/videos/se...B324FBD53D&FORM=VIRE

If you look closely, you can see 0.0300 written on the hanger; that's exactly the same as the one I just received from Kelbly's.

It's also fun to see that when Erik made that video, he was using a CM1500 and an Omega trickler. I had the same equipment then too. He (and I) has moved up from there since then.

As for the effect on precision, my gunbuilder and I discussed the same thought, but we thought that might depend on the primer being used. Some are harder than others and thus could have more erratic ignition issues with a shorter pin fall. He only had vague empirical data and was not keeping track of the types of primers in use. This was just an observation he had formed over time; no numbers, no details, no nothing.

So I suspect you are correct.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Okay, thanks.
Always learning something. Smile




“The terror of the Roman arms added weight and dignity to the moderation of the emperors. They preserved peace by a constant preparation for war; and while justice regulated their conduct, they announced to the nations on their confines, that they were as little disposed to endure, as to offer an injury.”
— Edward Gibbon, The Decline and Fall of the Roman Empire
 
Posts: 40714 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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I've had all my actions timed. I understand this stuff. My actions pin fall .255-.260, cock on close .005-.10. My actions cycle great.

Moving your trigger/trigger hanger will increase your pin fall at the expense of adding an additional .030 cock on close. Adding that much cock on close is not going to make for a very smooth cycling action. If it was my action, it would make a trip back to Kelbly. Change the cocking piece? Grind it to a desired cock on close. Maybe change triggers?
 
Posts: 2663 | Location: 9860 ft above sea level Colorado | Registered: December 31, 2008Reply With QuoteReport This Post
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My Panda Fclass is a cock-on-open design.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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This past weekend I swapped the trigger hangers and I cannot tell the difference either on bolt opening and closing or in the trigger pull. If there is a difference it eludes this old guy who has shot over 20,000 rounds in competition with that rifle.

I loaded up a ladder test yesterday and shot it at a local range where I am a member. I now realize that I really suck when shooting from a bench.

Anyway, I found a load that produces an MV of 2452FPS with an SD of 8.9. I'll try to refine the seating depth a little more but that's what I'll be using for the next match.

This MV reduces the drop @ 1000yards by 2MOA (from 35.4 to 33.5) and buys me an additional .2MOA of windage (from 6.3 to 6.1) according to JBM. I have to see what the recoil will be once on the ground.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Some update on my trials and tribulations.

The newer load sucked big time. It got to the target fine but it was grouping like a shotgun on the target; I could not achieve under 2MOA at 1000 yards. The first match was with my old load and I did quite well, but the next two matches were with the new load. The come ups were as predicted, close to 2MOA at 1000; but the grouping, yuck.

I decided to get back to my original, slower load and start tweaking the seating depth. Last week, I shot the 1000 yard match and tied for second, 2 point behind the leader for the whole match. I came in third on the first match, then the wind really started and I took second of the second match, off by one point and won the third match by one point. The winner also happens to be the current TSRA LR champ and he's also a really great guy. He also did very well at the Nationals, where I cratered.

This is coming together. Finally.
 
Posts: 3023 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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