§ Fitment Guide

Mac Allister Mac 50CC chain size & replacement chart

The Mac Allister Mac 50CC takes a .325" pitch, 1.5mm gauge chain. Below: every factory bar length with its exact drive-link count, cross-referenced to Oregon part numbers, plus the OEM parts list.

Fitment matrix

Bar lengthPitchGaugeDrive linksOregon chainsBars / combos
50cm .325" 1.5mm 21BPX078E21LPX078E

Source: Oregon part-finder (EU), retrieved 2026-07-06. Part numbers link to the manufacturer's spec page. Always confirm drive-link count against your current chain before ordering.

How to confirm the fit

  1. Read your bar. The pitch and gauge are stamped on the guide bar near the saw body — e.g. 3/8" LP .050".
  2. Count drive links. Lay the old chain flat and count the teeth that ride inside the bar groove. This number must match exactly; length in inches is not enough.
  3. Match all three. Pitch, gauge and drive-link count all have to agree with a row in the table above. Two of three is not a fit.
Measuring a chainsaw chain's gauge with a caliper

Watch: how to identify chain pitch and gauge

Oregon Products: Identifying Chain Pitch and Chain Gauge Oregon Products: Identifying Chain Pitch and Chain Gauge

Official video from Oregon Products, the manufacturer behind the cross-reference part numbers above.

Official Mac Allister resources

FAQ

What size chain does a Mac Allister Mac 50CC take?

The Mac Allister Mac 50CC runs a .325" pitch, 1.5mm gauge chain. Available bar lengths: 50cm. Match the drive-link count to your bar (see the table above).

How do I know which gauge my Mac 50CC chain is?

Check the number stamped on your guide bar near the tail, or measure the drive-link thickness with calipers. Common gauges for the Mac 50CC are 1.5mm.

Can I put a longer bar on my Mac Allister Mac 50CC?

Oregon lists 50cm bars for the Mac 50CC. Stay within this range — a longer bar than the engine is rated for cuts slowly and accelerates wear.