How can one reduce the linear shrinkage in polypropylene moulding without extending the cooling period?

holding pressure+
switching time to holding pressure-
if allowed, foam additive.

Thanx Ray, will try inc holding time & come back soon ! Wud foam additives reduce the stiffness of PP ?

Is a material change an option? Talc or mineral fillers can reduce shrink and increase stiffness. Potential to decrease price also.
If no, increase pack pressure, decrease tool temp, this will reduce shrink, lower gloss, may increase internal stresses and parts may warp after release of internal stress during any high temp testing.

Thanks so much, Mr. Robert ! I'll give your suggestions a try and come
back to you. MoC cannot be changed, which is a big constraint !!
Regards,
Mehul

Larger, thicker gate and more hold time.

AND like the others - Hold Pressure and lower Melt Temp.

We run one prouduct with poly-pro 24% cal, to control the part length without extending the cooling time,we run thermolators on the mold.

If the part is to long we increase the heat on the thermolator
If the part is to short we decrease the heat on the thermolator

Utilizing E-Dart on your mold to maintain consistancey or use Decoupled Molding Process and establish Melt temp and Part weights to mold good parts. Hope this helps.

INCREASE INJECTION PRESSURE, REDUCE INJECTION SPEED,INCREASE HOLD ON PRESSURE,INCREASE COOLING TIME AND CHECK PROPERLY COOLING LINE IS PROPERLY OK. REDUCE TEMPERATURE LIKE 190*C,180*C UNDER 200*C IF YOU CAN USE HOT RUNNER MOULD THEN REDUCE THE HRM TEMPERATURE ALSO. THEN YOUR PRODUCT IS OK.