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The burn rate listed in QL for Lil Gun is too low when used with loading densities of less than about 90%. I have found 0.9630 to work well (instead of the default 0.8550) from 40% to 85% load density.

This is because the burn rate of LG starts dropping as the case gets full. A plot of velocity vs. grains is nearly linear up to about 85% after which it rolls over and flattens out. As loads become compressed velocities will begin to drop. My guess is that the LG burn rate test was done near 100% load density.

My observations are based on chronograph readings of 22 Hornet, 218 Bee, 25-20, 32-20, 38 Spec and 45 Colt.

I bring this up because it can create a dangerous, or at least surprising load. For example, an esteemed handloader on another board has his own website where he lists some heavy LG loads for 218 Bee in a Contender. The loads he lists are way over those recommended by Hodgdon (the manufacturer). When I worked up 218 Bee loads for my Winch Mo 43, I found that I could not get anywhere near the other handloaders load without experiencing high pressure signs such as pierced primers and case/head separation. The reason for our differences is that he was using full case loads, and I was working up from much lower levels (in accordance with Hodgdons advice).

So be careful when using LG at less than 90% load density, as it will be faster than QL predicts and others may report. IMO, it is perfectly safe at less than 90%, if you make the necessary QL BR corrections and heed the mfr's guidance.


Last edited by ozzy the nuke; 07/12/09.
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Curious: How would the powder 'know' or respond to what the load density is? I can understand clearly a powder exhibiting varying burn rates at varying pressures, but load densities? Please elaborate.

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OK. Here is my theory. I have no proof. But see if you think it makes sense.

Pistol powders normally "flash." That is the entire charge essentially ignites at once and burns very quickly. Very fast powders are nearly burnt before the bullet even leaves the case.

Now consider LG. LG is a mixture of very fine grains, some of which are flat. It can compact tightly. If the load is loose, the primer flame can penetrate through the open spaces. The powder ignites all at once, and burns quickly. But if it is crowded, not all of it lights at the same time, and some of the burn is delayed. If it is compacted, it initially burns like a solid, and there is a substantial delay. I think that all ball powders do this more or less. It is well known that they should not be compressed. LG is so fine that it increases the effect.



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Works for me. I've never seen LilGun 'in person,' but I can follow what you propose.

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I'd like to know what loads you are using in the 32-20. I've ben looking for a max load of Lil'Gun behind the 115gr speer gold dot in a marlin 1894CL.


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Although I have tested some very heavy loads in 32-20 bolt action (Savage Sporter), I wouldnt dream of recommending them to others. And, for reasons I noted above, I don't prefer LG for max loads. I would suggest H110 instead. Having said that, you and your gun will probably survive a full case of either LG or H110 (about 15 grs). Probably....If you survive, expect near 2100fps and pressures in the 40ksi range. That is way over book max. I prefer limiting pressure to 25ksi in my Remington pump (mo 25). That is about 12.5gr of LG and 1900fps. My favorite loads are in the 1500fps range (10gr LG). If I need more power, I have plenty of other guns for that. I havent experimented with a Marlin, so I dont know what it will take. If I were you, I would start with a book load and work up until extraction becomes a little sticky, then back off.

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Thanks.
I plan to start with 9gr LG and work up to 1900fps. I should be able to reach that in the 22in barrel without pressures being too high.


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If you want to have some fun, try a case full behind a 60gr Gold dot. I have clocked them at 2800fps and pressures are just under 25ksi. Surprisingly, the accuracy was decent. They make a mess of anything they hit.


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