User talk:Zak Smith

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Hello Zak Smith, and welcome to Wikipedia! Here are some recommended guidelines to help you get involved. Please feel free to contact me if you need help with anything. Best of luck and happy editing!  ♥ Kylu  (talk • contribs • email • logs • count)
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I saw the edit to your userpage and decided it'd be nice to welcome you to our Wikipedia. Thanks for joining!

If you've got any questions, please don't hesitate to contact me. :)

~Kylu (u|t) 20:36, 26 May 2006 (UTC)

[edit] Beware of copyright

Hi, I have tagged the picture http://en.wikipedia.org/wiki/Image_talk:Schmidt_%26_Bender_P4_Fine_reticle.jpg for deletion and hope that it will be deleted from Wikipedia in the near future. The source of the picture I can no longer trace, but it surely did not come from your website. By the way I liked your work on the Sako TRG-42 and Accuracy International AWSM and have a question about the AWSM twist rate. According to the several years old AI brochure I have the AWSM .338 Lap. Mag. has a 1 in 10 in twist rate. Did you actually measure the twist rate of the AI AWSM you used or was it a special order job? If the rifle you used has a 1 in 11 in standard factory barrel this might be an interesting modification, since AI once solved an AWSM .338 Lap. Mag. feeding problem. Francis Flinch 10:13, 26 September 2007 (UTC)

[edit] Thanks & AI-AWSM Update

Hi, Thanks for pending it for deletion. It doesn't surprise me that you found the image somewhere else-- it just takes one person to copy/repost it without permission and then it gets harder to trace. For about a year I have been tagging the images with a copyright watermark, but those can be cropped off by offenders, etc.

On the AI-- I have measured the twist in my barrel at 1:11. It's a factory AI barrel from 2005. I am aware of the brochure, and I think that was an error-- new brochures say 1:11. I asked the importer about twist rates about a year ago, and they said that all the ones in recent history have been 1:11. (In the late 90's, there may have been another twist rate-- faster.) This would not have affected feeding, but the 1:11 was probably settled on as an optimum twist for the military ammunition, which is 250gr (Lapua Lock-Base last I heard). If you are interested in checking with the importer, you can contact Tac-Pro shooting center in Mingus TX, or get in touch with AI-UK directly.

Since long-range rifle barrels are a consummable item (338Lapua should last around 4000 rounds), when re-barrelling an AI-AWSM or TRG-42, it makes sense to consider a 1:10 twist barrel to enable use of the higher-BC .300gr Sierra MatchKing bullet. There is no problem using third-party barrels on AIs, as long as the gunsmith who fits it knows generally about the AI system.

If you have questions, don't hesitate to contact me via email- zak@computer.org Zak 16:04, 26 September 2007 (UTC)

Thanks for your update on the AI-AWSM twist rate. I will use it to correct the Wikipedia article on it. The feeding problems with the first AI-AWSM’s had nothing to do with the barrels but with lack of internal magazine length (CIP rules that .338 Lap. Mag. cartridges can be loaded up to 93.5 mm OAL, for the smaller .300 Win. Mag. CIP rules 84.84 mm OAL). AI solved that long ago.
Logical deduction learns that the also rather long 1:12 twist rate must work for 250 gr. projectiles. The 250 gr. Lapua Lock Base was selected by the Finnish Defense Forces (FDF) as standard issue for their 8.6 TKIV 2000 (= Sako TRG-42) marksmen. Finland is a coastal nation and has an arctic winter. The dense arctic air the FDF marksmen and their purveyor of .338 caliber long range bullets have to cope with will quickly exhibit any lack of adequate bullet stabilization. Your test results proved that the 1:12 twist rate was not tight enough to stabilize 300 gr. SMK’s in probably less dense air.
Defense forces can not select small arms projectiles solely on technical aspects. The .338 caliber Lock Base bullet is often selected by defense forces because the use of expanding bullets in international conflicts is prohibited by the Hague Convention.
Francis Flinch 12:49, 27 September 2007 (UTC)

Hi,

250gr works in 1:12 definitely-- the TRG-42 is issued with a 1:12 barrel. It turns out that at high altitude (e.g. 5000' here in Denver), the 300gr SMK can be shot accurately from both 1:11 and 1:12, however, I wouldn't bet on it worked at low altitude or low temperatures.

On the magazine length-- The current AI 338LM magazines will not take cartridges loaded to 93.5mm (3.68"). Factory Lapua ammunition is loaded to 3.600" and I think the AI mags will only fit somewhere out around 3.62 - 3.63-- I'd have to measure it again.

Zak 19:55, 10 October 2007 (UTC)

I checked the 93.5 mm (3.681 in) COAL (COAL = L6 in CIP nomenclature) for the .338 LM with the CIP CD-ROM Edition 2003. The Wikipedia .338 LM infobox COAL data coincided perfectly with the CIP provided data. Something that might not be very obvious, military organizations and other fire arms bearing government agencies do not legally have to comply with CIP rulings in CIP member states.
It nevertheless surprises me to read that you think your current AI magazines are about 0.05 in (1.27 mm) short to cope with maximum CIP legal L6 .338 LM cartridges. The VVN 2006 reloading guide mentions several .338 LM handloads at page 37 that would fit in your AI magazines, but it also mentions a Lapua Scenar reload that exploits the full CIP legal 93.5 mm (3.681 in) L6 length. If you can confirm that your 2005 AI magazines of your AWSM rifle have a sub CIP maximal L6 internal length this would be interesting to mention in the Wikipedia article.
Maybe the AI magnum action is lengthwise marginal for the .338 LM at its maximal L6, since I can not think of another reason why the magazines of your 2005 high end factory SWS are not totally compliant with the relevant CIP maximum cartridge dimensions. This might also shed some light on why several European armies opted for AI AWM rifles in its .300 Win. Mag. chambering or chose to buy the Sako TRG-42 in .338 LM instead of the AI AWSM. I would not speculate in Wikipedia articles, but things like this make me wonder about purchase policies.
The British military has started to claim a muzzle velocity of 936 m/s (3071 ft/s) for their .338 LM service cartridges (see L115A3). They must have started to exploit the .338 LM’s very high Pmax to attain this muzzle velocity out of 27 in barrels. AI will probably be delighted with the extra demand for replacement barrels.
Francis Flinch (talk) 18:45, 21 November 2007 (UTC)