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roysha
04-10-2024, 05:59 PM
I'm debating with myself whether to get a 16" or 20" barreled 17 HMR. The balance and handling are of really no consequence for this particular application. However, I do want to achieve, as near as practically possible, the suggested factory velocities in order to maximize the ballistics of the 17 HMR. Yes, I know the factory numbers come from the manufacturers test guns and is only a guideline which may or may not be reproducible in any given rifle, but it is, as far as I'm concerned, a starting point.

I have read various tables that purport to show the difference between the two is negligible. Most show a greater difference from round to round, from the same box of ammunition, than between the 16" and 20" lengths. A couple actually show the 16" equal to, or even a few fps faster than, the 20" barrel.

My question is: Has anyone here actually chronographed those barrel lengths? If so, what were you results? Yes, I realize that different barrels of equal length can/will give different velocities but I'm trying to establish a "trend" using information from everyday folks that don't have any skin in the game, so to speak.

cwtebay
04-10-2024, 06:11 PM
I have NOT chronographed these.
But I do believe these fellas do their homework from what I have seen.

https://www.bullberrylegacy.com/17-hmr-velocity-data#:~:text=Summary,average%20of%20the%2019%22%20 length.

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M-Tecs
04-10-2024, 06:34 PM
I have NOT chronographed these.
But I do believe these fellas do their homework from what I have seen.

https://www.bullberrylegacy.com/17-hmr-velocity-data#:~:text=Summary,average%20of%20the%2019%22%20 length.

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They did a nice job on their test. Cutting the barrel off is the only way to get meaningful comparison. Some barrels are "fast", and some are "slow". I've barreled and tested numerous 308 identical barrels I chambered for Palma shooting. A 100 FPS differences was common with consecutively numbered custom blanks and chambered with the same reamer and headspace.

dverna
04-10-2024, 08:19 PM
I have NOT chronographed these.
But I do believe these fellas do their homework from what I have seen.

https://www.bullberrylegacy.com/17-hmr-velocity-data#:~:text=Summary,average%20of%20the%2019%22%20 length.

Sent from my Pixel 5 using Tapatalk

Good post!!

Texas by God
04-10-2024, 10:19 PM
The 20” is four inches quieter than the 16” is all I know[emoji16]


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