I was doing a search for something else and this thread popped up and although it is a bit dated, I have an answer to the question. I have used both devices extensively on my small scale placer mine and in friend's lode mines. I started off using the Micro Blaster as it was more compact than the other larger and more expensive option that used a shotgun shell. The micro blaster worked pretty well, but it had its issues:
1. it uses a 5/16" SDS drill which in longer lengths is both expensive and difficult to find, also when drilling longer holes through rock, the 5/16" drill bit would wander a bit and make for a not so straight hole. Also because the bit was so small in diameter, it was my experience that the bits overheated quickly and were rendered worthless after a few minutes drilling which sucks for a $20- $50 drill bit.
2. The charges are NOT waterproof, and if they got wet they were rendered worthless. I was working around water all the time blowing up rocks in the creek.
3. Micro blaster sells two types of systems and I got the air powered one as I wanted to set off multiple charges at once. Their other system used a pull cord and could only do one charge at a time. I had issues with the air powered. I hike into my mining claim and because it was air powered, I needed to hike in a Gast air compressor and motor to run it. That's a lot of weight to be packing around, and Gast's don't come cheap. Because it was so heavy to move around I'd have to leave it there and there was always the chance that someone could come by and steal my expensive equipment. Another problem was if the air line got cut (sharp rocks when the get blown up) I was out of business AND I also experienced a lot of misfires because the head wasn't properly seated (see wandering drill bits), and the last issue about air powered was it only did 3 heads at a time max.
4. In my opinion, the charge wasn't big enough for the big rocks in my creek. It cracked the rocks, but I had to add a bunch more charges to blow up 6 foot diameter rocks.
5. The heads were heavy... not heavy in the big picture of things, but remember I am hiking stuff into my claim and I don't need a bunch of un-necessary weight on my back.
So in my experience, for a home handyman, not working in a wet environment, where you could drive to the job with all your needed equipment to use it and who had small rocks he wanted to detonate, the Microblaster worked fine. But for small scale mining, where equipment is packed in on your back, and larger rocks are involved, I think the Sierra Blaster is the better choice. I'm selling mine if anyone is interested, contact me. I think new, the system sold for $2300.
Sierra Blaster
A good friend of mine is a successful inventor/gold miner and when talking to him, I was lamenting to him the weaknesses of the Microblaster system to the small scale miner. He told me he could come up with a better idea and he designed the Sierra Blaster. I have spent a lot of time out in the field trying different versions of this device and I think he has finally come up with the holy grail of economically priced, contractor grade rock splitting devices. Over the last 2 years I have probably split no less than 300 4-6 foot diameter rocks with this device and I am amazed each time I do it. Here are my pros:
1. The charge is 10mm in size which is quite a bit bigger than the MB charge. We tried both larger and smaller sizes and 10mm was the best for detonation and ease of use. The 10mm SDS drill apparently dissipates heat better and the drills last quite a bit longer and they don't wander. He manufactures his own drills and they cost around $10 each. His drill lengths range from 6"- 48"...... 48" you say? Why would anyone want a 48" drill? To drill in very wet situations where everything gets wet.
2. Did I tell you the charge is waterproof? I have blown up lots of rocks under 36" of water (using the 48" drill to drill the hole). It literally sounds like two rocks hitting each other when detonated underwater.
3. Electrically powered detonators. Because of this there are several options of using electricity for using this device. If you are a contractor and you are lugging around a small generator, SDS drill, etc... he has a 25 foot cord that connects to the heads with lots of safety features. There is literally no way the charge will "accidently" go off. Another aspect of electrically powered charges is this system can do up to 18 heads at once. I haven't seen that, but I'd like to... talk about making mince meat of rocks.... And the best part for the small scale miner (who has to pack stuff on his back into the claim) is he sells an option that has a 9v battery powered ignitor to set off the charges. Lightweight and compact.
4. Heads- he sells both steel heads and aluminum heads. If you are a contractor get the steel heads, they are heavy and you don't need much extra weight to hold them into the hole while detonating. If you are a small scale miner like me, I want the aluminum heads as they are light weight to carry into the claim and if I need extra weight to hold the head in the hole during detonation.... I have a river full of head-sized rocks to set on top of the blasting heads.
5. It's been so long I don't remember the price of the MB cartridges, but the Sierra Blaster Cartridges run around $2 each.
6. When using the Sierra Blaster, you don't need an ATF blasting license. These charges are incredibly safe. I have a video of the inventor holding a charge in his hand and detonating it and nothing happens to his hand (don't try this at home)- it just looks like a sparkler went off. Yet, put that same charge in a 6 foot diameter rock and it will split it right down the middle.
And the best part of the Sierra Blaster? You can buy a system for $725.
The cons? I haven't found any yet....
Whichever system you choose, these are great tools for cracking rocks that are too big to move, lift or are in the way. Yesterday a local contractor called me to crack a rock that was under a foundation he was working on. He didn't want to use a backhoe to possibly damage the foundation, and they tried a jack hammer and apparently the rock was swallowing the bits without actually splitting the rock, so I was called and in 10 minutes with $2 worth of charges his problem was solved.
I am a huge proponent of this device and I can see all sorts of uses for it.
