16 - Mastering Sweet Spot: Boost Accuracy in 3 Steps

[@mrsd2photo]

Great video. Never thought of batch weighing the pellets. Excellent idea. With respect to a regulator, an Air Arms independent gunsmith told me that a regulator does not improve consistency to any great degree. All it achieves is to increase the shot count.

[@hftshooter]

Thanks for watching and commenting. 👍

[@rivit90]

Im not into hft anymore but do use a s400 classic for paper punching , Your findings are almost identical as my own , I fill to 170 bar and shoot it down to 110 bar , This gives me exactly 60 shots with no change of impact point vertically/horizontally. Cracking guns the s400

[@hftshooter]

They certainly are. Thanks for sharing. 🙂👍

[@thetraindriver01]

Nice, well explained, thank you 👍

[@hftshooter]

Glad it was helpful! 🙂👍

[@martindudley7866]

Great video, really interesting and the first I've seen covering the subject! A very un-patronising well done from me! When I have my next day up at Pete's Farm, I'm going to try out my Revere from full charge to power-drop and see what the results are. As standard, the Revere has a regulator and I wonder if its main contribution is to the consistency of fps over the claimed shot count. One thing I absolutely love about the FX radar chrono is the ability to email the whole shot string data; a quick import to google sheets and I'll have the whole dataset without the grief (for a non-typist) of entering it all manually. Once again, your vid has set the thought wheels in motion. Big ol' cheers and keep up the good work!

[@hftshooter]

Hi Martin, many thanks. As your Revere has a regulator it won't have a sweet spot. The whole point of the regulator is to keep the muzzle velocity as constant as possible. The FPS shouldn't drop off until your cylinder pressure falls below the reg pressure. Hope that helps.

[@mandj102]

Very good informative video once again. I do look forward to your uploads….

[@hftshooter]

I appreciate that! 🙂👍

[@Happy-Me.]

Good video. I've found on my HW100 although regulated that its sweet spot is from around 180 bar to 120 which is a wide range.

[@hftshooter]

Good stuff. 🙂👍

[@hftshooter]

👍

[@alanmullock381]

Well explained! Me and technology are a bad mixture(old school graph paper and a few hours concentration 😡)😁👍👍👍👍👍👍👍👍👍👍👍👍👍

[@hftshooter]

Thanks Alan. You can do it!

[@alfredotito2143]

Very good video. In your rifle, does the velocity change if the temperature changes? thanks greetings

[@hftshooter]

I intend to test that, but I think it must do due to changing air density.

[@Dave-Lefever]

Cracking video

[@hftshooter]

Thanks! 🙂

[@Steve-Cross]

That is very interesting. It makes you wonder if the cost of a regulator is worth it, if you already have a quality rifle. Perhaps it just helps with the shot count. Personally, I just want my rifle to be as accurate as possible. 😊

[@hftshooter]

Good points Steve. If a rifle has a consistent muzzle velocity then a regulator isn't going to improve shot count, the two go hand in hand. For the most part shooters don't need as many shots as they think. Thanks for your comment. 😀👍

[@edwardthompson3213]

Great video .am i right in thinking it was the first 15 shots on the s400 that you used as your example of the total spread and deviation. Would you not get an even better result further up the shot count in say the middle of the sweet spot or am i missing sumething excellent video veary informative and a surpriseing result 👍

[@hftshooter]

Hi Edward, the 10 shots I used for the spread and deviation were from shot 28 of the shot string. This is from where the pressure had dropped to 170 bars which is the normal fill pressure I use for the rifle.

[@MichaelEdwards2]

Excellent content as usual but how do you get the pressure off the gauge on the bottle with out purging and opening the fill valve

[@hftshooter]

Good question Michael. Once you've charged the rifle you close the cylinder valve and leave the pressure relief valve closed. The gauge and whip remain pressurised and in effect become part of the rifle cylinder, so as the rifle uses air the gauge shows that drop in pressure. Hope that helps.

[@MichaelEdwards2]

@@hftshooter perfect, thank you. Going to do the same in the week and see what my results are.

[@hftshooter]

🙂👍

[@MrTaz0079]

You need a FX Chrono, you can record all the shots ftp on your phone every time,

[@hftshooter]

Thanks for the advice. I'm quite happy with my chronograph thanks. It's not overpriced and I never have any shot errors! 😉

[@FeathersMcGraw1]

Very interesting. How is the standard deviation figure created? Is it the percentage of the total results? ie 2.7%

[@hftshooter]

There is a formula, but it's quite complicated and difficult to reproduce in a comment. Try googling it and you'll see what I mean. I just used the built in function on my excel spreadsheet to calculate it.

[@FeathersMcGraw1]

@@hftshooter Many thanks.

[@dttrandom]

Just a comment on methodology. Often the most extreme of the data points at high and/or low ends get tossed out as outliers before the average/spread/standard deviation are calculated. The unregulated numbers has a low outlier in the #1 spot, and the regulated numbers have an outlier at the #5 spot. Those should be tossed out and then calculated. If you do that, the chart for the regulated is flatter than the unregulated. I didn't run spread and standard dev, but from a flatter chart those numbers would also be better.

[@hftshooter]

You can't remove data points because they interfere with the results you wish to achieve. If your rifle produces high and low spikes during testing it's likely to continue to do so when you're shooting. I'm sorry, but the idea of removing extreme data points to provide more constant results is totally unscientific and ridiculous. If you remove any data points you don't like then your results are simply invalid.

[@dttrandom]

It's not about removing data points you don't like. It's removing extreme outliers that throw off the analysis. The outlier can be caused by any number of factors that aren't related to the product you're testing. In the case of shooting, it could be a slight wind, a bad pellet that just happens to be in the group you pulled out, or the shooter. Contrary to being unscientific as you think, it is the more scientific method, especially when you're doing just one test and using just one user. If you repeated your test 10-20 times then including all data points make more sense. Even more sense is having multiple people doing the test that you set up. By the way, I think you mistake that data points that don't agree with a preconception are what I said should be tossed out. It's not multiple data points being tossed out. It's looking at the single lowest point and the single highest point, and how far they are from the rest of the combined group. If they're much further apart from the group than the other shots in the group is from each other, then they're outliers that should be considered to be tossed out. From a shot group of ten, keeping in an outlier can throw off the analysis much more than keeping in one out of 100 shots. Chemists and physicists employ the method of tossing out the extreme outlier at either end as well. There are many tutorials on statistical analysis that you can watch if you want to learn more. Not trying to criticize you. You're trying to help other shooters, especially beginning shooters (like myself), so I'm grateful for your channel. But if you want to help them with good info, you should have an open mind that you too can improve how you're doing your testing which results in better info. @@hftshooter​

[@fxpeter22]

The comparison between unregulated and regulated was not balanced as you picked the best 10 shot string out of a string of 114. The point of a regulator is to give better consistency over the full charge from max fill right down to the reg set pressure. Using your own numbers, had you compared the results for all 114 shots the unregulated rifle would have a spread of 34.1fps and a standard deviation of 6.32 whereas the regulated rifle would most likely be consistent over the whole shot string. Considering the 45 shots you picked for the HFT course (22-66) they return a spread of 16.4fps and SDev of 3.72. In both instances the regulated rifle produced better results than the unregulated rifle. With a regulated rifle you also remove the worry of slipping outside the “sweet spot”when shooting. I hope this gives a broader comparison of the true difference between regulated and unregulated.

[@hftshooter]

The point of the video was to show how to find the sweet spot on an unregulated rifle, i.e. the fill pressure from which the most consistent string of shots can be taken. In this instance, the sweet spot was from a 170 bar fill so it was the string of 10 shots from that point that I used in the comparison. If it's the correct sweet spot then that string should always be the most consistent 10 shots, that's the point of the exercise; no funny business. As a competitive HFT shooter I'm only interested in the most consistent 30 shots. For benchrest it would be 25 shots and for hunting it's often less than 10! If I need some sighters for the zero range I will fill an extra 5 bars or so to cover those before the event. I'm really not that interested in how the rifle performs further down the shot string. If I'm plinking and I notice the poi begin to change I simply refill. It is common practice for a 10 shot string to be used to calculate velocity spread and standard deviation and for those results to be used to compare rifles. A regulated rifle by its very nature shouldn't have a sweet spot, so any 10 shot string above the regulator pressure should be representative of the rifle's performance if it's a well functioning regulator. Taking this into account I think it was a fair comparison and was included to show that not all unregulated rifles need to have a regulator added. I hope that clarifies my intent.

[@fxpeter22]

@@hftshooter Jeff, The point of your video was not lost in fact you very capably demonstrated how to determine the “sweet spot” but the comparison with the regulated rifle results were unbalanced. We agree that “A regulated rifle by its very nature shouldn't have a sweet spot, so any 10-shot string above the regulator pressure should be representative of the rifle's performance if it's a well functioning regulator.” In fact, 10/20/30/40 shots strings should be consistent. However, by your own admission as an HFT shooter you are only interested in the best 30 (thirty) shot string for a competition. Using your results there is not one 30 shot string that is equal to or better than the 12.1 fps spread you obtained from the regulated rifle. If I were to be pedantic the best 30 shot string in your results is shots 24-53 which returned 12.2 fps spread but you would have to be a special person to replicate that start point on a competition day. I am not trying to belittle your efforts, but you suggested that your unregulated rifle would not benefit from having a regulator fitted! Probably not if you are only ever going to fire 10 shots from the exact same start pressure every time, but yes it would, if you want better results from more than 10 shots and less worry about where the pressure indicator is before you start shooting. This is all very academic considering the small shift in POI for a few FPS considering all other variables that affect the shot, but we need to be thorough with the details.

[@daniellewis5413]

Get it regulated on worry's

[@hftshooter]

I'd like to see a regulated S400 that could improve upon 8.6 ft/sec spread and a standard deviation of 2.7!