Built around how you train.
Every kit includes SCUSA Polymer Clips. Choose the system that fits your round count and range habits.
900 Rounds Ready
- 90 Polymer Stripper Clips
- Color-Coded System included
- SLB™ Loading Block
StripLULA
- 90 SCUSA Polymer Clips
- SLB™ Loading Block
- StripLULA® Speed Loader
- Full color-coded system
Organized
- 450 Polymer Clips total
- Full armory-scale system
- 2x SLB@ Loading Block
- 20x MIL-SPEC Desiccant packs included
- StripLULA®
How Long Does 5.56 Ammo Last in Storage? A Complete Shelf Life Guide
Temperature, humidity, container type, and desiccant use — what the military knows about long-term 5.56 storage and how to apply it to your stockpile.
The Short Answer: Longer Than You Think
Modern brass-cased 5.56 / .223 ammunition stored correctly will reliably function for 50+ years. Military stockpiles from the 1960s and 1970s still test within spec today. The rounds themselves don't expire — the container environment does.
The four variables that determine shelf life are temperature, humidity, container seal, and clip material. Get those right and your ammo will outlast everything else in your storage system.
Factory cardboard box: 2–5 years in real-world conditions — cardboard absorbs moisture, offers zero seal, and fails in any humid environment.
Steel surplus can, no desiccant: 10–20 years — rust and seal degradation are real risks over time.
Airtight polymer can + desiccant + polymer clips: 50+ years, guaranteed.
A cardboard box in a Houston garage in August isn't storing ammo — it's cooking it. The AC50C system costs less than $15 and removes every variable that kills long-term storage.
What Actually Degrades Ammunition
The brass case, lead core, and copper jacket are chemically stable for decades. What actually degrades is the propellant powder and the primer compound — both are sensitive to moisture and temperature cycling.
| Threat | What It Damages | Prevention |
|---|---|---|
| Moisture / humidity | Primer, propellant, brass corrosion | Airtight can + desiccant |
| Temperature extremes | Propellant breakdown at 150°F+ | Store below 85°F, avoid attics/vehicles |
| Temperature cycling | Condensation inside sealed containers | Store in climate-stable environment |
| Rust from steel clips | Brass case corrosion, primer contamination | Use SCUSA polymer clips — won't rust |
| UV / direct sunlight | Polymer component degradation | Store away from windows |
The Military Standard for Long-Term Storage
The US military stores 5.56 in sealed steel containers with desiccant at controlled temperatures and retrieves it decades later in functional condition. The civilian equivalent is simpler and more accessible — the MTM AC50C with a Desiccare desiccant pack does the same job at a fraction of the cost and weight.
- Temperature: 55–75°F — consistency matters more than coolness
- Humidity: below 50% RH inside the sealed container
- Light: no direct sunlight on polymer components
- Location: off the floor, away from exterior walls
- Container: airtight with intact gasket seal
Why Polymer Clips Outlast Steel in Storage
USGI steel stripper clips rust. In a sealed container with micro-humidity — even with desiccant — steel clips develop surface oxidation over years. That rust transfers directly onto the brass cases of your stored rounds. It doesn't necessarily make the ammo non-functional, but it contaminates your storage environment and can affect feeding reliability.
SCUSA polymer clips are chemically inert. No rust, no oxidation, no contamination — regardless of how long they sit sealed in a can. Pull them out in 20 years and they look and function exactly as packed.
Chemically inert. No rust. No oxidation. Identical condition after 20 years in sealed storage.
Develops surface rust over time even in sealed storage. Transfers oxidation to brass cases.
Desiccant — The Only Consumable in the System
Everything else in your storage system lasts indefinitely. The desiccant is the one component that needs periodic replacement. Desiccare 1/2 unit packs last 2–3 years under normal conditions before they reach saturation and need replacing.
- Check desiccant indicator color — replace if pink or white
- Inspect can gasket — should be supple, not cracked or compressed flat
- Check latch function — should close firmly with a positive click
- Inspect label — replace if faded or illegible
- Reseal and return to shelf — total time per can: ~2 minutes
Signs Your Ammo Has Been Compromised
| Sign | Likely Cause | Action |
|---|---|---|
| Green or blue verdigris on brass | Moisture exposure over time | Test fire — most still function. Replace desiccant. |
| Rust stains on brass from clips | Steel clip oxidation transfer | Switch to polymer clips. Test reliability. |
| Loose primer / primer falling out | Severe moisture or impact damage | Do not fire. Dispose of properly. |
| Reduced velocity / hang fires | Propellant degradation | Retire the lot. Check storage conditions. |
Properly stored 5.56 in an airtight polymer can with a desiccant pack and polymer clips will outlast you. The system works. The only failure mode is neglecting the desiccant replacement — and that's a 2-minute job once every 2–3 years.
Build the Long-Term System
SLB Gen2 + 30 stripper clips. Start building your long-term storage system today.
Shop CORE Kit →SLB Gen2, StripLULA, all three clip colors, desiccants, and ammo can. Everything for long-term storage.
Shop ARMORY MAX →Replace your steel clips with polymer. No rust, no oxidation, indefinite storage life.
Shop Clips →Frequently Asked Questions
Can I store ammo in a garage or attic?
Attics are the worst possible location — temperatures regularly exceed 130–150°F in summer, which accelerates propellant breakdown. Garages are marginally better but still subject to wide temperature swings and humidity. A climate-controlled interior space — basement, closet, safe room — is always preferable.
Does steel-cased ammo store as well as brass?
No. Steel cases are more susceptible to corrosion and the lacquer coating can crack over time, compromising the case seal. Brass-cased 5.56 is the standard for long-term storage. If you're building a serious stockpile, stick to brass.
Should I vacuum-seal ammo for extra protection?
Vacuum sealing adds marginal benefit beyond an airtight can with desiccant. The main risk it introduces — static discharge near primers — outweighs the benefit. Stick with the AC50C + desiccant system.
How do I know if my desiccant is still working?
Desiccare desiccant packs include a color indicator — blue or yellow when active, pink or white when saturated. Check it annually when you open the can for inspection. If it has changed color, replace it before resealing.
180 color-coded clips + dual SLB loading blocks + StripLULA® + 20× MIL-SPEC desiccants.
Load faster.
Organize smarter.
SCUSA polymer stripper clips, loading blocks, and MIL-SPEC desiccants. Everything you need in one kit.
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