Re: RE: RE: [John Muir Trail] Bear Vault
- On Thu, Oct 3, 2013 at 10:13 AM, Rick Martyn <rickmartyn@...> wrote:With some thought toward the volume of food choices combined with repackaging, I find 100 cu inches per person per night to be fairly easy to achieve and can usually manage at about 85 cu inches per person per night.Interesting rule of thumb. 100 cubic inches = 1.64 liters. I pretty easily get 10-12 days of person-food in my 16L (999 cubic inch) custom 16 inch Bearikade, even with use of some higher-volume choices.
I fit 6 days into a BV450, which is much smaller than a BV500. Three bits of advice: repackage, repackage, repackage.
I agree all the good resupply options are frustratingly clustered in the north half of the trail. I resupplied at Onion Valley. Only 14 miles round trip, and it worked well.
---In email@example.com, <firstname.lastname@example.org> wrote:
I don't see how anybody can fit 8 days of a sustainable diet (3500-3700 calories/day, 125 grams protein) AND their smellies (soap, mosquito, and sun goops) into a BV500. On the other hand, room in the pack is precious, and I think a custom made extended Bearikade would take up to much space.
Which begs for a re-supply point on the trail between MTR and Whitney Portal that doesn't cost hundreds of dollars or involves a day's hike out to the temptations of "civilization".
---In email@example.com, <firstname.lastname@example.org> wrote:Unless your going to bypass a few areas in the southern half of the JMT may have to carry a canister unless Ursack gets approved (see the latest info below). Berikades are the lightest available and will save you about 10oz (BV500 vs. Bearikade weekender). If you can fit 8-10 days food in your BV500 you should be able to do it in a Bearikade Weekender (it's smaller but you can just use a bigger hammer). Bear canisters are only required on about 50 miles of the JMT (per Ursack). 2014 may be the year Ursack is approved so stay tuned.
July 12, 2013No word yet from IGBC.
June 5, 2013
SUCCESSFUL GRIZZLY TEST. Ursack was tested in two configurations by the IGBC at the Grizzly and Wolf Discovery Center in West Yellowstone on May 30, 2013. I was there for both tests. Check out a video excerpt on our Bear Test Videos page. This is a slightly newer version (since April 2013) of the Ursack S29 AllWhite which is sewn with Spectra thread. Ursack did extremely well. The IGBC test protocol requiresthat a product must survive 60 minutes of bear contact, which is defined as: "biting, clawing, pounding, rolling, compressing, licking or scratching." More than one Grizzly worked on the Ursacks, but the clock only runs while a bear is actively engaged. In one test, at least three (possibly four) bears attacked a baited unlined Ursack tied about five feet up a tree trunk. At the end of 60 minutes, the Ursack was fully intact with no punctures or tears. I easily untied it from the tree and opened it without the use of tools. The current IGBC published protocol states that: "If the product is not breached within the required 60 minutes of bear contact time, it will be considered to have "passed" the captive bear test."
In the other test, an Ursack with an aluminum liner was placed on the ground and not tied to anything. Sam and Illie--a brother sister tag team (Sam weighs 950 pounds)--attacked the Ursack. This bag was torn after approximately forty three minutes of contact. My interpretation is that the grizzlies were able to use their massive shoulder strength and claws to compromise the Ursack. Black bears are very different. They do not have the shoulder strength (no hump) or size of grizzlies and their claws are different. We have tested lined Ursacks on the ground with captive black bears and the Ursacks have easily survived. In the thirteen years we have been in business selling across North America (including Alaska and Canada), I have never heard of a grizzly compromising an Ursack.
It is my very strong belief that Ursack, whether lined with aluminum or not, tied up a tree or not, would pass a captive bear test with black bears. I suspect that an Ursack (aluminum lined or not) tied up a tree to minimize claw and shoulder advantage would survive a captive grizzly test.
The IGBC has not issued its official evaluation yet. We hope to receive approval within a couple of weeks. Stay tuned. I will post video excerpts of the IGBC test soon.On Wed, Oct 2, 2013 at 8:12 AM, Kyle Arn <arn.kyle@...> wrote:I was wondering if there are any other allowed alternatives to the bear vaults. I have a bear vault and I'm planning on doing the southern half of the JMT next year and that thing is heavy even empty. With 8-10 days of food in it is going to feel like I'm caring a beer keg on my back. Are there any bear resistant bags out there?Kyle