RMS 29/40-120

I'm planning to use this case for my Ventris and Argent. I'd like to know what would be the best used reload kit for tis casing? I've had it for years and have yet to use it. Also best vendor to get the reloads from?

Thank for your help on this.

G-64 is my all time favorite for that RMS. Get them from buyrocketmotors.com

For hazmat free reloads, I tend to order from sirius rocketry and buyrocketmotors.com. If one is out, the other may have it.

Other vendors include Chris' Rocket Supplies (Link) and Wildman Rocketry (Link).

G64 is a classic

G76 is nice and peppy

G138 is an ANIMAL!!! IMHO one very underrated motor

Thanks so much for all your help. What I have found which I'm sure is typical is the prices from vendor to vendor varry. That doesn't bother me. Bu I also noticed that reload can cost a bit more than a single use motor. The advantage is of course no Hazmat fee.

Wildman with the membership knocks 35% off retail price. Thats on all Hobbyline hardware and reloads.

$14 for the G reloads, $12.60 for the F reloads.

They will be present at our ROC event Roctober at Lucerne where it would make sense to buy them there save on shipping.

You'll want the 7 second delay for the G53, 64, 76 reloads for most PS-II. Ventris likes a little longer. 8-8.5 on the 64 and 76.

Theory said:

G138 is an ANIMAL!!! IMHO one very underrated motor

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But requires level 1 cert ....

Bat-mite said:

But requires level 1 cert ....

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true that

Bat-mite said:

But requires level 1 cert ....

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And has the tendency to blister your case..

Nytrunner said:

And has the tendency to blister your case..

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Really? I’ve flown several with no issues.

Call me lucky I guess

Theory said:

G64 is a classic

G76 is nice and peppy

G138 is an ANIMAL!!! IMHO one very underrated motor

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G64 and G76 reloads are my favourites for this case. As pointed out above, the G138 is an HPR motor.

Yes the G138 is an HP load...

The OP asked for the “best load” for the 40/120 case, not the best mid power load.

In my experience the G138 is one solid load, and one worth flying

Theory said:

Yes the G138 is an HP load...

The OP asked for the “best load” for the 40/120 case, not the best mid power load.

In my experience the G138 is one solid load, and one worth flying

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Yup, but people who are not certified and haven't looked into the laws regarding HPR often see "G" and think they are good to go. Never hurts to remind folks that some G motors and all sparky motors require HPR certification.

understood - and good point

The G64 is my goto load for the RMS 29/40-120. I really miss the G33.

As for the G138, Aerotech recommends wraping a layer of masking tape on the top end of the fuel grain to prevent blistering.

n3tjm said:

As for the G138, Aerotech recommends wraping a layer of masking tape on the top end of the fuel grain to prevent blistering.

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Very interesting, is that around the circumference of the grain at top, around the circumference of the liner at top, or over the top face of the grain?

That’s how I do it.

n3tjm said:

As for the G138, Aerotech recommends wraping a layer of masking tape on the top end of the fuel grain to prevent blistering.

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Interesting. Too bad that as far as I can see, the printed instructions don't mention this at all. https://aerotech-rocketry.com/uploads/432354f2-0ee9-4ecf-a2b2-f5b1b1978953_rms_29_g138t_hp_20036.pdf

The G 138 does not have a liner. You slide the single propellant grain into the case then, add o-rings and insulators.
I suspect that people experiencing blistered cases are running 10-14 sec delays. The delay is actually doing the damage more so than the propellant. Reason why; once the propellant burns away there isn't much left of the casting tube the propellant occupied. The longer the delay; the more you cook your casing. If I could; I would put a plug in the delay well of the forward bulkhead and run electronics for this load. Semi-solution: wrap the propellant grain in blue painters tape.... The entire length of the grain.

It was later added after a few people had issues.

mikec said:

Interesting. Too bad that as far as I can see, the printed instructions don't mention this at all. https://aerotech-rocketry.com/uploads/432354f2-0ee9-4ecf-a2b2-f5b1b1978953_rms_29_g138t_hp_20036.pdf

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I use the tape and a good coat of Dow 111

Theory said:

G64 is a classic

G76 is nice and peppy

G138 is an ANIMAL!!! IMHO one very underrated motor

Click to expand...

Only problem with the G138 is Haz Mat and requires certification.

Interesting that the video explains putting the wrap of tape at the 'top' end of the grain, but when they assemble it, the taped end is by the nozzle. Someone making the video wasn't paying attention.